Introduction

In July 2015, the P5+1—the United States, United Kingdom, France, Russia, China, and Germany—reached a diplomatic agreement with Iran to roll back and significantly limit the Iranian nuclear program in exchange for the lifting of economic sanctions. The Joint Comprehensive Plan of Action (JCPOA) was the result of years of meticulous diplomatic negotiations and represented an historic compromise between two long‐​standing adversaries, the United States and Iran. At the time, the Obama administration presented the agreement as a strict nonproliferation agreement that would extend Iran’s so‐​called breakout time—the time it would take Iran to “sprint” to the creation of a useable nuclear weapon—from a few months to a year or longer. Many also hoped that the JCPOA could help to reduce bilateral tensions and quiet calls for U.S. military action against Iran for the foreseeable future. The unexpected election of Donald Trump in 2016 dashed these hopes. With renewed tensions and open debate within the Trump administration as it conducts a “comprehensive review of our Iran policy,” the future of the JCPOA and of U.S.-Iranian relations is uncertain. 1 There are certainly many options for the Trump administration if it wishes to take a more confrontational approach to Iran, four of which are examined in this paper. Yet each is difficult, costly, and carries far higher risks than continuing a policy of engagement.

The JCPOA has been successful, placing strong restrictions on Iran’s ability to engage in even peaceful nuclear development. Iran removed 98 percent of its stockpile of enriched uranium, dismantled two‐​thirds of its uranium enrichment centrifuges, disassembled the core of its heavy water reactor (a potential source of weapons‐​grade plutonium), and converted two major enrichment sites into peaceful research facilities. In addition, Iran agreed to engage in uranium enrichment exclusively at a single facility—the Natanz complex—and to produce only low‐​enriched uranium for 10 years. Because uranium must be enriched to 90 percent for use in a nuclear weapon, Iran’s agreement to restrict enrichment to 3.67 percent constitutes a significant barrier to weapons development. Iran also agreed to limit its stockpile of low‐​enriched uranium to 300 kilograms for 15 years, making it extremely difficult to covertly enrich excess material. 2

To ensure compliance with the JCPOA’s restrictions, Iran agreed to submit what remained of its nuclear program to what Georgetown University’s Ariane Tabatabai describes as “the most intrusive inspections regime ever voluntarily agreed to by any party.” 3 International monitors perform daily inspections of all of Iran’s declared facilities, with some facilities subject to 24‐​hour video surveillance. As critics note, these inspections and many of the deal’s other restrictions eventually expire, phased out over the next 10 to 25 years. 4 As part of the deal, however, Iran rejoined the Nuclear Nonproliferation Treaty (NPT) and ratified its Additional Protocol, a provision that mandates inspections of Iran’s civilian nuclear facilities. In doing so, Iran made a commitment to never become a nuclear weapons state and agreed to monitoring under the NPT indefinitely, far beyond the life of the JCPOA.

Indeed, more than two years after the adoption of the JCPOA, Iran is in full compliance with the deal. Though there has been some debate about the interpretation of certain issues—Iranian missile testing and the extent of U.S. sanctions relief—the deal continues to be implemented by both sides. As of this writing, the International Atomic Energy Agency (IAEA) has reported eight times that Iran is meeting its obligations under the deal. 5 Even the Trump administration, despite public denigration of the agreement, has formally certified that Iran is fulfilling its JCPOA commitments. In exchange, economic sanctions related to Iran’s nuclear program have been lifted, including United Nations and European Union sanctions on Iran’s energy sector and a variety of U.S. secondary sanctions related to Iran’s financial and energy sectors. 6 In addition, Iran has regained access to wealth stored in offshore banks previously interdicted by sanctions. 7

Growing Opposition in Washington

Nonetheless, the change in presidential administration has altered the political climate surrounding the nuclear deal in Washington, D.C. There have been prominent calls from both within the Trump administration and outside it to kill the JCPOA. As a candidate, Donald Trump himself repeatedly boasted that his “number‐​one priority is to dismantle the disastrous deal with Iran,” which he described in his typical hyperbole as “the worst deal ever negotiated.” 8 The recertification process (required every 90 days) has become increasingly politicized as a result: in July 2017, some advisers persuaded the president to refuse certification of Iran’s compliance with the JCPOA, only for other advisers to succeed in persuading him, at the last minute, to accept the IAEA’s conclusions and certify compliance. 9 Trump told journalists following the episode that he intends not to repeat the incident, reportedly informing White House staff that “he wants to be in a place to decertify 90 days from now and it’s their job to put him there.” 10 As David S. Cohen, former deputy director of the Central Intelligence Agency (CIA), notes, President Trump’s “reported demand for intelligence to support his policy preference to withdraw from the Iran nuclear deal risks politicizing intelligence analysis, with potentially grave consequences.” 11

Calls to end the deal have also come from outside the administration. In July, Sens. Tom Cotton (R-AR), Ted Cruz (R-TX), David Perdue (R-GA), and Marco Rubio (R-FL) wrote a letter to Secretary of State Rex Tillerson to “urge that you not certify … that Iran is complying with the terms of the [JCPOA].” 12 John Bolton, United Nations ambassador under George W. Bush and an early candidate to be Trump’s secretary of state, called for bombing Iran’s nuclear facilities months before the JCPOA was signed. 13 In July 2017, he wrote, “withdrawing from the JCPOA as soon as possible should be the highest priority.” 14

Opponents of the deal have little factual basis for their arguments: the IAEA has repeatedly found Iran in compliance with the deal’s restrictions, and the Joint Commission of the JCPOA has not identified any violations. 15 Instead, opponents typically argue that Iran is violating the “spirit” of the deal, pointing to Iran’s ballistic missile tests or its support for violent groups throughout the Middle East. 16 Yet the JCPOA was narrowly written specifically to exclude non‐​nuclear questions; it was never intended to solve all problems in the U.S.-Iranian relationship. Ironically, if any JCPOA signatory is in violation of the deal, it may be the United States. 17 At the G-20 summit in July, President Trump reportedly urged fellow world leaders to stop doing business with Iran, an action that violates the American commitment under the JCPOA to “refrain from any policy specifically intended to directly and adversely affect the normalization of trade and economic relations with Iran.” 18

President Trump appears determined to undermine the JCPOA. The administration is considering using the deal’s “snap inspections” provision—which allows inspectors to demand access to undeclared sites in Iran reasonably suspected of illicit enrichment activity—to make Iran appear noncompliant. 19 In the absence of any clear evidence of illicit enrichment activity, Iran would likely decline the Trump administration’s demand to inspect undeclared military sites, allowing the White House to portray Iran as violating the deal. As Mark Fitzpatrick, executive director of the International Institute for Strategic Studies, notes, this approach is “the route that White House political operatives suggest as a way to meet President Trump’s pre‐​determination not to again certify that Iran is in compliance, even when the facts clearly say otherwise.” 20 This approach also plainly misuses the relevant provisions of the JCPOA: as Daryl Kimball, director of the Arms Control Association put it, the Iran deal’s “special access provisions were designed to detect and deter cheating, not to enable [a] false pretext for unraveling the agreement.” 21 The administration appears to be simply “seeking trumped up reasons to sink [the] Iran deal.” 22

The Trump administration’s approach to Iran approximates the Bush administration’s approach to Iraq in the lead up to the 2003 invasion. Fitzpatrick compares the two situations, noting that “unfounded assumptions, false claims, and ideologically‐​tinged judgements are driving a confrontational approach that could well lead to another war in the Middle East.” 23 As in the case of Iraq, the risk exists for politicization of intelligence findings. As Steve Andreasen and Steve Simon, both former members of the National Security Council, describe in a recent op‐​ed in the New York Times: “It’s a good bet that [administration officials] will cherry‐​pick facts to give the president what he wants: an excuse to scuttle the Iran deal.” 24

President Trump’s commitment to a harder line against Iran—independent of the nuclear deal—is obvious, though the Trump White House’s vicious internal power struggles suggest clear differences inside the administration on the best approach. In June, for example, the New York Times reported that the administration was ramping up a covert action program against Iran, and that “Mr. Trump has appointed to the National Security Council hawks eager to contain Iran and push regime change, the groundwork for which would most likely be laid through CIA covert action.” 25 Yet Trump’s National Security Adviser H. R. McMaster fired the council’s former senior director for intelligence, Ezra Cohen‐​Watnick, in August. Cohen‐​Watnick had previously expressed to administration officials “that he wants to use American spies to help oust the Iranian government.” 26 Along with Derek Harvey, who was the administration’s top Middle East official on the National Security Council, Cohen‐​Watnick had also advocated broadening U.S. involvement in the Syrian civil war as a means of pushing back against Iran. McMaster likewise fired Harvey in July 2017.

Prominent Iran hawks remain in the administration, and some go well beyond arguing for abrogating the JCPOA to make the case for a regime change policy toward Iran. In June, Tillerson testified before the House Foreign Relations Committee that the administration intended to “work toward support of those elements inside of Iran that would lead to a peaceful transition of that government,” 27 though other high‐​level administration officials have denied this is current policy. 28 While he was a member of Congress in 2016, Trump’s current CIA director, Mike Pompeo, publicly called for the United States to “change Iranian behavior, and, ultimately, the Iranian regime.” 29 Senator Tom Cotton (R-AR)—known to be close to the Trump administration—likewise has stated that “the policy of the United States should be regime change in Iran.” 30 Defense Secretary James Mattis as recently as June described Iran as “the most destabilizing influence in the Middle East.” 31

Outside the federal government, other hawkish voices have also made forceful calls for regime change. Soon after Trump was inaugurated, the well‐​connected conservative think‐​tank Foundation for the Defense of Democracies (FDD) submitted a memo to Trump’s National Security Council that argued for “coerced democratization” in Iran, a euphemism for regime change. 32 John Bolton said in a speech in July, “The behavior and the objectives of the regime are not going to change, and therefore the only solution is to change the regime itself.” 33

The Costs of Confrontation

The debate on Iran in Washington today includes many options, some—though not all—of which begin with killing the JCPOA. Deliberately scuttling the JCPOA would have negative ramifications. The international community and Iran, recognizing U.S. intransigence, could conceivably continue to uphold the nuclear deal without the United States, isolating the United States from allies and handicapping its pursuit of unrelated diplomatic initiatives, notably the question of North Korea’s nuclear program. Alternatively, U.S. termination of the JCPOA could motivate Iran to unburden itself from the deal’s restrictions, expel international monitors, and begin once again to pursue a nuclear weapons capability in earnest. Either possibility puts the United States in a weaker, more dangerous position. Given the momentum in Washington behind pursuing a more hostile approach toward Iran, this policy analysis will explore the likely costs and consequences of four different approaches to confronting Iran, whether as alternatives to the JCPOA or supplementary to it.

The first approach we assess is applying economic pressure in the form of ratcheting up sanctions on Iran, including those the international community agreed to lift under the JCPOA. The second approach looks at the options for challenging Iranian influence in the Middle East, particularly its proxies in Iraq and Syria. The third approach considers the viability of what is called “regime change from within,” where the United States would support internal opposition groups in an effort to undermine or overthrow the government in Tehran. The fourth and final approach we evaluate is military action against Iran, most likely in the form of limited airstrikes against Iranian nuclear or other military facilities. We conclude by proposing a fifth strategy for the Trump administration: uphold U.S. commitments under the JCPOA, refrain from adding new sanctions, and engage with Tehran where U.S. and Iranian interests overlap. There is no silver bullet that can solve the problems in the U.S.-Iranian relationship, but continued engagement carries lower costs and a higher chance of success than any of the other approaches examined here.

Option One: Economic Sanctions

Opponents of the JCPOA frequently argue that they could negotiate a better deal through the aggressive use of U.S. sanctions. These sanctions would be extraterritorially applied, forcing European companies to adhere to U.S. law, in theory making Iran willing to concede more of its nuclear program or to make other security and governance concessions. For example, former Connecticut senator Joe Lieberman proposed in December that President Trump “designate the entire Iranian Revolutionary Guards Corps as a foreign terrorist organization … support legislation in Congress punishing sectors of the Iranian economy … propose measures to curb Iranian access to U.S. dollars … and then to walk away, with cause, from the JCPOA.” 34 Such arguments are not restricted only to those who wish to abrogate the JCPOA. Various authors argue that while there are no grounds to “tear up” the deal, the president and Congress should nonetheless seek to impose new sanctions on Iran related to its regional activities and support for the Assad regime in Syria.

Indeed, Congress has already acted in this regard, passing an extensive sanctions bill in July 2017, including North Korean, Russian, and new Iranian sanctions. The bill, “Countering America’s Adversaries through Sanctions Act,” targets a number of new individuals and entities—particularly in relation to Iran’s ballistic missile program—and includes an arms embargo and several new reporting requirements. 35 Congress made last minute changes to the bill to ensure that it did not technically violate the JCPOA, 36 yet as Senator Bernie Sanders (I-VT) pointed out when justifying his vote against the bill: “I believe that these new sanctions could endanger the very important nuclear agreement that was signed between the United States, its partners, and Iran in 2015. That is not a risk worth taking.” 37 Sanders is correct; new sanctions on Iran for its missile programs and human rights abuses raise tensions within the framework of the JCPOA while adhering to the narrowest possible definition of its terms. In response to the new sanctions bill and the threat of further sanctions, Iranian leaders voted to increase the state’s military budget and threatened to restart the nuclear program, highlighting the escalatory potential of new sanctions. 38

Opponents of the JCPOA support the imposition of new sanctions, particularly the designation of the Islamic Revolutionary Guard Corps (IRGC) and IRGC‐​associated businesses, often with little regard for whether new sanctions could torpedo the deal or worsen relations. Council on Foreign Relations Senior Fellow Ray Takeyh has repeatedly said renewed sanctions are the first step in a broader strategy of pressure on Iran, arguing that “we must return to the days of warning off commerce and segregating Iran from global financial institutions. Designating the Revolutionary Guards as a terrorist organization and reimposing financial sanctions could go a long way toward crippling Iran’s economy.” 39 Likewise, the editors of the conservative National Review advised the Trump White House to abrogate the deal through sanctions: “Better to declare an end to this diplomatic farce … and establish a robust sanctions regime that might actually force Tehran to change its ways.” 40

Problem #1: No International Consensus

The central problem with this option—whether as a replacement for the JCPOA or in addition to it—is the utter lack of international support. Though often overlooked, the JCPOA is in reality a multinational arms control agreement, negotiated by the P5+1, the five permanent members of the United Nations Security Council, plus Germany. The other parties to the deal have been unequivocal in affirming that Iran is indeed abiding by its commitments under the deal. On August 3, a spokeswoman for European Union foreign policy chief Federica Mogherini told a press conference: “So far, we consider that all parties have been implementing their commitments under the deal.” 41 Sergei Lavrov, Russian foreign minister, likewise confirmed Iran’s compliance and questioned the Trump administration’s motives, saying in August that the Trump administration “continue[s] calling these agreements wrong and erroneous, and it’s a pity that such a successful treaty is now somewhat being cast into doubt.” 42

European support for the deal is strong. As Carl Bildt, former prime minister of Sweden, noted in an opinion piece in August, canceling the deal would be a nonstarter in Europe: “Europe would certainly not go along with this, for one because it would risk undercutting the elaborate inspections systems that the agreement depends on. But primarily because Europe has seen that the deal actually works … and Europe has absolutely zero appetite for a new cascade of conflicts in a region on its doorstep.” 43 As a result, European leaders are also keen to prevent the imposition of further non‐​nuclear U.S. sanctions that could potentially undermine the deal. Indeed, on July 11, Mogherini told reporters: “The nuclear deal doesn’t belong to one country; it belongs to the international community. We have the responsibility to make sure that this continues to be implemented.” 44

It is unlikely that any additional U.S. sanctions would be successful without multinational support. The United States has long had an extensive array of sanctions focused on Iran, including on weapons procurement and development, U.S.-Iranian trade, and terrorist financing. Yet the long‐​term effect of these sanctions on the Iranian economy was relatively minimal prior to 2005. Technology sanctions have undoubtedly been successful in slowing progress on nuclear and missile‐​related projects but have done little to impact Iran’s import and development of conventional weapons. 45

Two changes in the mid‐​2000s substantially increased the efficacy of sanctions on Iran. First, the Treasury department aggressively pursued a strategy of outreach, lobbying (and threatening) foreign banks to ensure that U.S. sanctions would be adhered to extraterritorially. Second, the European Union decided in 2012 to embargo Iranian oil exports. This decision was motivated by increasing concerns over Iran’s nuclear program, even though it was politically and economically costly for the Europeans. In 2010 alone, Iran’s exports to the EU totaled $19 billion, 90 percent of which were energy related. 46 By March 2013, Iran’s oil exports had dropped from 2.5 million barrels per day to 1 million barrels per day, resulting in an Iranian budget deficit of $28 billion that year. 47 While U.S. sanctions alone were relatively ineffectual, these punitive economic costs helped to drive Iran to the negotiating table.

Proponents of increased sanctions therefore typically advocate for more assertive enforcement of secondary sanctions penalties against European and Asian companies. A recent report from the Washington Institute for Near East Policy, for example, called for the United States to step up the extraterritorial enforcement of existing sanctions on terror financing and IRGC‐​affiliated companies, arguing that enforcement and public warnings could discourage European companies from re‐​entering the Iranian market. As Stuart Levey, at the time undersecretary for terrorism and financial intelligence, described the use of extraterritorial sanctions prior to the JCPOA: “Those who are tempted to deal with targeted high‐​risk actors are put on notice: if they continue this relationship, they may be next.” 48 Yet the decision to sanction Iran was costly for European companies. A number of companies, most notably French energy company Total, which signed a $5 billion investment deal with Iran and with China’s National Petroleum in July to develop the South Pars gas field, have begun to re‐​enter the market following the successful conclusion of the JCPOA. 49 In the absence of any concrete evidence of Iranian cheating on the deal, European and Asian governments are likely to push back strongly against new U.S. barriers to trade and investment in Iran, and on the excessive extraterritorial application of existing sanctions.

Problem #2: Sanctions Rarely Produce Policy Change

Another problem with sanctions is that they are rarely successful in producing policy change. Indeed, though targeted sanctions may impose costs on the targeted regime, it is less clear that these costs actually produce policy change. 50 Proponents of increased sanctions point to high profile successes like the JCPOA, while skeptics point to the many cases, from Syria to Zimbabwe, where sanctions have failed to produce policy change. More broadly, academic studies have repeatedly shown sanctions to be ineffective in achieving policy change. As Arne Tostensen and Beate Bull note in the journal World Politics, “The voluminous literature that has accumulated over the years tends to conclude that sanctions are rarely effective, even though exceptions have been documented.” 51 In one of the earliest broad‐​based studies of comprehensive sanctions, for example, researchers found an average sanctions success rate of only 34 percent. 52 Even the research on more recent “smart sanctions,” which are presumed to be more effective thanks to their “targeted” nature, shows that they are also largely ineffective. A wide‐​ranging study of United Nations targeted sanctions found them to be effective in only 10–20 percent of cases, 53 while another survey of post‐​9/​11 U.S. sanctions found them to be effective in only 36 percent of cases. 54

Policy change is especially unlikely when sanctions do not have clear, attainable goals or when the issue is of prime national security importance to the target state. 55 Sanctions focused on economic issues such as trade often seem to be qualitatively different than those focused on security. 56 When University of Chicago’s Robert Pape examined sanctions as an alternative to the use of force, he found they had only been successful in around 5 percent of national security–related cases. 57 Sanctions also tend to fail when they are unilateral; as the Washington Institute’s Katherine Bauer notes, even with the power of U.S. extraterritorial sanctions, “there are limits to U.S. jurisdiction and the ability to compel foreign compliance.” 58 Further sanctions on Iran thus fall into a worst‐​case scenario: security‐​focused sanctions with no clear goals other than securing “a better deal” or weakening the Iranian regime. In the absence of strong support from European or other Security Council nations, there is very little chance that further sanctions will compel Iran’s leaders to capitulate.

Option Two: Challenging Iranian Influence in the Region

An alternative option is a deliberate strategy of challenging Iranian proxies throughout the Middle East. That option would not necessarily require the Trump administration to abrogate the JCPOA. Indeed, as Brookings Institution Senior Fellow Daniel Byman recently noted in congressional testimony: “Because the JCPOA … has put Iran’s nuclear program on the back burner, there is an opportunity to focus on Iran’s support for militant groups and other problems Iran causes in the region.” 59 This approach runs counter to Washington’s current regional strategy: though there are arenas where the United States is engaged in hostilities with Iranian‐​associated proxies—such as U.S. support for the Saudi‐​led campaign in Yemen—America’s anti‐​ISIS campaign typically means that it is de facto fighting on the same side as Hezbollah and other Shi’a militias. The most moderate alternative proposals call for U.S. support for regional allies, such as military and diplomatic support for a peace settlement in Yemen designed to split the Houthi rebels from Tehran’s limited support. 60 Other options include increased maritime presence to help disrupt Iranian arms shipments. 61 Still others call for building the capacity of regional actors: one recent report from the Center for a New American Security suggests maintaining U.S. influence in Iraq and increasing U.S. logistical support for the conflict in Yemen, in hopes of marginalizing Iranian influence in those conflicts. 62

However, there are also a variety of more aggressive proposals. Two senior former administration officials on the National Security Council, Derek Harvey and Ezra Cohen‐​Watnick, were reportedly in favor of direct U.S. military action against Iranian proxies in Syria. 63 Escalating clashes between U.S. troops and militias in southern Syria in recent months, including U.S. airstrikes on several militias, suggest that such clashes will happen even in the absence of a formal policy change. Several recent policy papers also make the argument for a more formalized anti‐​Iran strategy in Syria, often using proxies to challenge Iranian‐​allied groups. The Washington Institute’s Nader Udowski, for example, argued in June 2017 for “a new U.S. policy, the chief component of which should be a strategy targeting Iran’s Quds force and its Shi’a militias.” 64 Similarly, Max Peck of the Foundation for Defense of Democracies has argued that the Trump administration should seek to codify in law that the United States seeks the overthrow of the Assad regime in Syria, and “increase the costs of Iran’s engagement by maintaining the pressure on Assad … through its support for the armed opposition.” 65

Perhaps the most bellicose option is actively increasing U.S. participation in the war in Syria and Iraq. A report from the Institute for the Study of War (ISW) called for the United States to “seize and secure a base in southeastern Syria … create a de facto safe zone … then recruit, train, equip, and partner with local Sunni Arab anti‐​ISIS forces.” The report called for American troops to “fight alongside” these forces. 66 The goals would include not only “defeating al Qaeda, as well as ISIS,” but also “expelling Iranian military forces and most of Iran’s proxy forces from Syria.” This strategy extends to Iraq: as a follow‐​on report argued, America should also “take urgent measures to strengthen Iraqi Prime Minister Abadi,” and work to minimize Iranian influence in Iraq. 67 Though the extent of American military involvement varies widely across these proposals, they all share a common theme: direct or indirect military action against Iranian proxies in Syria, Iraq, Yemen, and elsewhere.

Problem #1: An Anti‐​Iran Axis?

The central problem with this approach is that there is no coherent anti‐​Iranian axis in the Middle East to rely upon in a campaign to challenge Iranian influence in the region. Indeed, observers have often described the region using sectarian narratives—portraying conservative Sunni states in conflict with Iran’s more revolutionary Shi’a axis—that are largely exaggerated.

For example, despite Saudi efforts to form a united regional front against Iran, the conflicts of the Arab Spring have frequently seen the states of the Gulf Cooperation Council (GCC) act against each other’s interests. 68 In Syria, the conflict between Saudi and Qatari proxies helped to radicalize and doom the anti‐​Assad opposition, while a Qatari‐​Emirati rivalry fueled the Libyan conflict. Today’s GCC crisis only serves to highlight this problem: though clearly motivated by a desire to rein in Qatar’s independent foreign policy, the Saudi and Emirati embargo has in reality driven Qatar closer to Iran and Turkey, undermining a common GCC front. 69

Other regional attempts to form anti‐​Iranian movements have likewise failed. A widely‐​publicized Saudi Arabian attempt in December 2015 to create an Islamic Military Alliance to fight terrorism—which pointedly included no Shi’a majority states—has largely failed to develop since that time. 70 Nor is there any guarantee that regional partners will actually promote U.S. interests if the United States increases its support; the actions of allies in the region have all too often served to destabilize and worsen conflicts in Syria, Yemen, and elsewhere, rather than improve them.

Indeed, the lack of a solid anti‐​Iran coalition among existing U.S. partners—capable of achieving America’s often expansive foreign policy goals—is a key reason why the most extreme options for regional confrontation with Iran often involve fabricating an effective anti‐​Iranian bloc from whole cloth, whether that is the creation of a “credible and moderate Syrian opposition,” a regional “multinational Joint Task Force with Arab partners targeted at countering … the IRGC,” or “a new Syrian Sunni Arab partner … to conduct population‐​centric counterinsurgency.” 71 Each of these options is likely to fail. Previous U.S. efforts to create regional coalitions to fight terror groups have been largely unsuccessful. The 2014 collapse of the Iraqi army in the face of ISIS advances is also a salutary lesson; years of training commitments and substantial blood and treasure on the part of the U.S. military were not enough to overcome deeper societal problems like corruption. 72 Without coherent, effective local proxies, and given the major political differences that divide U.S. regional allies, any attempt to build an anti‐​Iranian force or coalition in the region is likely to falter.

Problem #2: Blowback, Leading to Ever Deeper U.S. Involvement

A strategy of regional pushback against Iran is also likely to pull the United States more deeply into a variety of regional conflicts and increase the risks of blowback to U.S. troops in the region. The United States is already heavily overcommitted in the Middle East, with tens of thousands of troops engaged in conflicts in Iraq, Syria, Afghanistan, Libya, and Yemen, and stationed at permanent bases elsewhere throughout the region. Indeed, despite the Obama administration’s attempts to draw down American commitments to Middle Eastern conflicts, the number of troops engaged in fighting Middle East conflicts has been increasing again since 2014. 73 A stepped‐​up campaign against Iranian proxies throughout the region will require further troop increases, both in direct combat roles and to train and support local forces.

It is these troops who will bear the brunt of any Iranian military response to this strategy. Several hundred U.S. troops were killed by Iranian‐​associated groups in Iraq during the post‐​invasion occupation, a number likely to rise in any new conflict with these groups. 74 And while Hezbollah has been largely occupied in recent years with fighting on behalf of the Assad regime, if faced with a concerted campaign against it by U.S.-allied forces, it is likely to respond with the kind of asymmetric attacks that have characterized their long‐​running conflict with Israel. 75 Indeed, one potential response to a concerted attack on Iranian proxies throughout the region is retributive attacks on Israel; during the 2006 war, Hezbollah enjoyed substantial success against Israeli forces, disabling a number of tanks and even an Israeli warship. 76 The potential for Iranian retaliation against U.S. troops, regional partners, or shipping in the region suggests that a strategy of regional confrontation with Iran will not make the region safer or more stable, but will instead introduce additional conflict and uncertainty.

Option Three: “Regime Change from Within”

Another possible option for dealing with Iran is an explicit U.S. policy of regime change. This is not a new idea; for decades, hawks in Washington have called for regime change in Tehran. Justifications have ranged from the 1979 hostage crisis to Iran’s nuclear program in the mid‐​2000s to the anti‐​regime protests known as the Green Revolution after 2009. 77 Yet the failure of U.S. regime change campaigns in both Iraq and Libya to produce a stable, democratic state has led most proponents of regime change to back away from overt military options and instead suggest that the Trump administration pursue “coerced democratization” or “regime change from within.” In this approach, the United States would pressure the Iranian regime and simultaneously back groups that oppose it—whether the exiled extremist National Council of Resistance of Iran (NCRI), pro‐​democracy Green Revolution factions, or ethnic minorities within Iran—a strategy advocates often compare to Reagan’s support for civil society groups in the Soviet Union. As Reuel Gerecht and Ray Takeyh argue in a Washington Post op‐​ed: “Today, the Islamist regime resembles the Soviet Union of the 1970s … if Washington were serious about doing to Iran what it helped to do to the U.S.S.R., it would seek to weaken the theocracy by pressing it on all fronts.” 78

Another proponent of “coerced democratization,” the Foundation for Defense of Democracies’ Mark Dubowitz, urged President Trump to “go on the offensive against the Iranian regime” by “weakening the Iranian regime’s finances” through “massive economic sanctions,” while also “undermin[ing] Iran’s rulers by strengthening pro‐​democracy forces” inside Iran. 79 This option appears to be gaining traction in the Trump administration’s ongoing Iran policy review and has received public support from Tillerson. CIA Director Mike Pompeo also favored such an approach during his time in Congress. Yet there are important reasons to doubt that such a strategy would actually yield constructive results in Iran or benefit U.S. national interests.

Problem #1: Regime Change Rarely Works

Regime change often fails, particularly when it is covert. According to one study of covert regime change operations by the United States during the Cold War, such efforts succeeded only one‐​third of the time. 80 Indeed, as an administration official said in August, “With Iran, they are looking at regime change but coming up empty. There are no good plans, no decapitation strikes possible.” 81 Arming or funding for local insurgencies also rarely succeeds; a leaked CIA report commissioned in 2012 found that most past attempts to covertly arm insurgencies had minimal impact on long‐​term outcomes and often backfired. 82

Even when successful in unseating one government and establishing another in its place, foreign‐​imposed regime change “generally does not improve relations between interveners and targets. Rather, it often makes them worse,” according to Georgetown University’s Alexander B. Downes and Boston College’s Lindsay A. O’Rourke. 83 Changing the leadership of a state typically fails to alter that country’s perception of its interests, and foreign‐​imposed regimes tend to diverge from the preferences of the intervener as they begin to face domestic political pressures. Contrary to the depiction of many regime change advocates, the Iranian regime enjoys substantial public support, and the population would not welcome a U.S.-imposed government. Any new regime that tried to implement policies that reflect U.S. interests instead of Iranian interests would “attract the ire of domestic actors,” leading to an unstable government viewed as illegitimate by the population. 84

Research shows that “when a country overthrows another’s government, it increases the likelihood of civil wars and usually doesn’t establish a democracy.” 85 The recent experiences of the United States in Iraq, Afghanistan, and Libya only confirm this finding. Sixteen years of U.S. military presence have done little to stabilize war‐​torn Afghanistan. 86 The war in Iraq essentially destroyed the Iraqi state, killing hundreds of thousands of Iraqis and displacing millions more. More than 4,400 U.S. troops were killed in combat, and more than 30,000 were wounded, with direct costs estimated to exceed $2 trillion and indirect costs as high as $4 trillion. 87 A widespread insurgency and civil war led to the rise of the Islamic State, prompting further U.S. intervention to fight against the group. In Libya, the U.S. choice to overthrow the regime of Muammar Gaddafi on humanitarian grounds resulted in a lengthy civil war and the deaths of more Libyans than would likely have perished without the intervention. 88 The likelihood of successful regime change and a subsequent stable, democratic state in Iran are vanishingly small.

Problem #2: A Lack of Good Candidates

Though regime change proponents highlight a variety of groups inside Iran as potential candidates for U.S. support, none are truly viable. The exiled opposition group Mujahideen‐​e‐​Khalq (MEK) (or its political wing, the NCRI) is one such example. The MEK began in the 1960s and 1970s as a paramilitary Marxist‐​Islamic resistance group opposed to the former Shah of Iran, the authoritarian ruler put in power following a 1953 coup sponsored by the United States and Great Britain. The group allied with Saddam Hussein during the 1980s Iran‐​Iraq War, and analysts widely agree that it is an undemocratic group that has no popular support inside Iran. 89 Indeed, the MEK has largely tried to win external support for its agenda of regime change in Iran. Until 2012, it was even designated a terrorist organization by the U.S. State Department and had lobbied hard over the years to win support from prominent current and former U.S. officials to have that designation removed. 90 It has won primarily the support of those who favor a hardline approach to Iran, such as former CIA directors James Woolsey and Porter Goss, former New York City Mayor Rudolph Giuliani, former governors Howard Dean and Ed Rendell, former U.N. Ambassador John Bolton, and former House Speaker and close Trump confidant Newt Gingrich. Yet in the absence of popular support outside certain Washington circles, backing the group in a bid to overthrow the Iranian regime would likely fail. 91

Regime change advocates also suggest supporting the so‐​called Green Movement that emerged amid the protests over the contested Iranian presidential elections in 2009. Unfortunately, according to Ariane Tabatabai and Madison Schramm, the Green Movement “essentially faded away a few months after the elections” and “was never a cohesive faction.” 92 Green Movement leaders Mir Hossein Mousavi and Mehdi Karroubi remain under house arrest in Iran today, and have made clear that their goal was to dispute the 2009 election results, not to overthrow the government. In fact, the best hope for the Green Movement is to avoid association with the United States; whatever popular support it continues to have would quickly evaporate with any whiff of U.S.-backing for regime change. As Michael Axworthy of the University of Exeter writes, “Given the long history of foreign meddling in the country (the CIA‐​inspired coup that removed Prime Minister Mohammad Mosaddeq in 1953 is just one example), any suspicion of foreign backing is political poison in Iran.” 93

The third option—seeking to stoke discontent among Iran’s minority populations—is similarly infeasible. Iran’s ethnic minorities include Kurds (10 percent), Baluchis (2 percent), Arabs (2 percent), and Azeri Turks (16 percent). 94 But Iran is not a country beset by ethnic, cultural, and religious cleavages in the way the former Yugoslavia was. Neighboring Iraq, with its mix of Shia, Sunni, and Kurds, was a comparatively disjointed state held together by a powerful centralized dictatorship. Iran is very different. Any strategy that seeks to foment political upheaval in Iran via these various minority groups ignores the fundamental cohesion that characterizes Iran as a national unit. 95 If anything, such an approach would be more likely to bolster Iranian nationalism than to subvert it. As Vali Nasr, dean of the Johns Hopkins School of Advanced International Studies and an Iranian‐​American, told the New Yorker in 2008, “Iran is an old country—like France and Germany—and its citizens are just as nationalistic. The U.S. is overestimating ethnic tension in Iran … working with the minorities will backfire, and alienate the majority of the population.” 96

Option 4: Direct Military Action

Direct military action against Iran is the least likely of the options being considered under the Trump administration’s policy review. Indeed, the focus on nonmilitary options among Iran hawks is likely a response to the widespread distaste among the American public for engaging in another open‐​ended regime change war in the Middle East. Yet some have argued that the Trump administration should “rebuild military leverage over Iran,” including “contingency plans to neutralize Iran’s nuclear facilities,” engage in regional military exercises, and direct the U.S. navy to “fully and responsibly utilize rules of engagement to defend themselves and the Persian Gulf against rising Iranian harassment.” 97

There are various contingencies in which U.S. policymakers may face a decision on the use of military force against Iran, whether it is a purposeful strike against Iran’s nuclear facilities in the wake of U.S. withdrawal from the JCPOA, or a more gradual escalation following military confrontations in Syria, the Gulf, or elsewhere. As the Trump administration considers these options, however, it would do well to remember that the lack of good military options was the key reason behind the Bush and Obama administrations’ decision to pursue diplomacy with Tehran in the first place.

Problem #1: An Illegal War?

The United States should only undertake military action against another state if its core security interests are threatened. Yet there is no plausible near‐​term scenario in which Iran poses a direct threat to the U.S. homeland. Nor do Iranian actions in the Middle East pose a significant threat to U.S. interests in the region. Taking military action against Iran to thwart the purported threat of its nuclear program would harken back to the preventive war doctrine adopted by the Bush administration after the September 11th terrorist attacks and codified in the 2002 National Security Strategy. 98 Though proponents of military action often describe such action as “preemptive,” one RAND report notes that “generations of scholars and policymakers have defined preemption more restrictively,” limiting it to cases of imminent threat. 99 This is a crucial difference; as the authors highlight, international law holds that truly preemptive attacks are an acceptable use of force in self‐​defense, while preventive attacks are not. As the historian and former Kennedy administration adviser Arthur Schlesinger Jr. put it when criticizing the Bush administration’s case for war against Iraq, this doctrine of preventive war “is alarmingly similar to the policy that imperial Japan employed at Pearl Harbor, on a date which, as an earlier American president said it would, lives in infamy. Franklin D. Roosevelt was right, but today it is we Americans who live in infamy.” 100 With no imminent threat from Iran, there is no legal justification for direct military action.

At the very least, the Trump administration is constitutionally obligated to seek approval from Congress for any military action against Iran. Trump himself may disagree. He previously declined to seek or secure congressional authority for his missile strike on a Syrian military base controlled by the Assad regime in April 2017 and has repeatedly made public statements arguing that military action should be kept secret to preserve the tactical advantage of a surprise attack. If Trump does seek congressional approval for military strikes on Iran, he is likely to face strong opposition from many Democratic members of Congress and at least some Republicans. Senator Chris Murphy (D-CT) argued in February that “Trump and his most radical advisers are begging for war with Iran. This would be a disaster of epic scale, perhaps eclipsing the nightmare of the Iraq war.” 101 Congressional Democrats, already concerned about the administration’s domestic policy proposals, are unlikely to cut him a blank check on Iran.

Problem #2: Escalation Is Inevitable

Even small‐​scale military attacks on Iran—whether targeted strikes on nuclear facilities or clashes with Iranian forces in the Gulf or elsewhere—are likely to lead to escalation. In March 2012, the Pentagon held a classified war simulation “to assess the repercussions” of an Israeli attack on Iran’s nuclear facilities. The results showed that such a targeted strike would provoke immediate Iranian retaliation against U.S. military bases and naval assets in the region, drawing the United States into “a wider regional war.” 102 General James Mattis, now Trump’s secretary of defense, was then head of Central Command and supervised the war game. The New York Times reported that Mattis told aides a strike “would be likely to have dire consequences across the region and for U.S. forces there.” Following a similar war game in 2004, retired Air Force Colonel Sam Gardiner concluded, “There is no military solution for the issues of Iran.” 103

It is not clear that a narrow or targeted strike is even possible. To strike Iran’s nuclear facilities, the United States would also need to bomb Iran’s air defense systems and command and control facilities, which itself carries risks of escalation. Writing in 2006, retired General Thomas McInerney suggested one such plan for attacking Iran’s nuclear facilities, requiring a massive commitment of 700 aircraft, 500 cruise missiles, and 28,000 bunker‐​buster bombs in the initial 36–48 hours. 104 Moreover, airstrikes of this kind, to accomplish any long‐​term objective, could not be limited to a single one‐​off mission. As explained in a 2012 study by the Iran Project, a nongovernmental organization founded to improve official contacts between the American and Iranian governments, for targeted strikes to “fulfill the stated objective of ensuring that Iran never acquires a nuclear bomb, the United States would need to conduct a significantly expanded air and sea war over a prolonged period of time, likely several years.” 105

Under bombardment from the world’s most dominant military superpower and uncertain of U.S. intentions, Iran would be likely to engage in retaliatory strikes against U.S. bases and military assets in Iraq, Syria, Bahrain, Qatar, and the United Arab Emirates. Iran’s Shahab‐​3 intermediate range ballistic missile can hit targets up to 2,000 kilometers away, while its Soumar cruise missile can potentially hit targets up to 2,500 kilometers away, meaning all U.S. forward‐​deployed bases in the Middle East and at least some bases in Europe are within range for conventional retaliation. 106 Likewise, the potential for asymmetric retaliation should not be underestimated. As Afshon Ostavar of the Naval Postgraduate School notes, “While Iran’s neighbors have poured billions of dollars into conventional weaponry, Iran has invested in comparatively cheap proxy forces that have proven effective in numerous theaters.” 107 Proxy groups such as Hezbollah or even Iran’s Quds force, a special unit of the IRGC, could engage in terrorist attacks against U.S. forces or allies in the region.

Anything beyond a limited military strike would have even more dire and counterproductive consequences. Taking military action to topple the Iranian regime, for example, would require a massive, lengthy, and costly military commitment. America’s experience in Iraq should be instructive in this context: Bush administration officials and their allies in the think‐​tank community and news media made bold predictions about the ease with which America would win the war, that Iraq would be reborn as a functioning democracy, and that the costs to the United States in lives and dollars would be minimal. These predictions proved wrong. In addition to bolstering Iran’s strategic position, the war helped to destabilize the region and to exacerbate America’s terrorism problem. A 2006 National Intelligence Estimate concluded that “the American invasion and occupation of Iraq … helped spawn a new generation of Islamic radicalism.” 108 The war had “become the ‘cause celèbre’ for jihadists, breeding a deep resentment of U.S. involvement in the Muslim world and cultivating supporters for the global jihadist movement.” 109

A large‐​scale ground war in Iran would be immensely damaging. Comparisons to Iraq are illuminating. The U.S. invasion was initially successful against a relatively ineffectual Iraqi military with approximately 389,000 men under arms. But U.S. forces have struggled in the years since to control territory, build a functioning Iraqi state, and deal with mass insurgency among the population of around 37 million. In comparison, Iran has a larger (about 523,000 active duty) and more effective military, a bigger population (80.3 million), and territory more than three times the size of Iraq. 110 A study by the Iran Project concluded: “If the United States decided to seek a more ambitious objective, such as regime change in Iran or undermining Iran’s influence in the region, then an even greater commitment of force would be required to occupy all or part of the country.… Given Iran’s large size and population, and the strength of Iranian nationalism, we estimate that the occupation of Iran would require a commitment of resources and personnel” greater than the costs of the wars in Afghanistan and Iraq combined. 111

Problem #3: Unintended (Nuclear) Consequences

A direct military attack on Iran, whatever the specific goals, is likely to be counterproductive in terms of nuclear nonproliferation. Military action short of regime change cannot eliminate Iran’s nuclear program or the knowledge behind its existence. 112 Given U.S. interventions in recent years, even targeted strikes may be seen by Tehran as a precursor to more intensive military action that must be deterred. A 2010 Defense Intelligence Agency study concluded that the main goal of Iran’s military strategy is regime survival, with a key focus on deterrence. 113 As Kenneth Pollack, a former CIA and National Security Council analyst, noted in 2006: “The Iraq example coupled with the North Korea example probably is part of the motivation for some in Iran to get a nuclear weapon.” 114 The 2011 U.S. intervention in Libya only intensifies this dilemma for Iran; Muammar Gaddafi voluntarily gave up his nascent nuclear program before being removed by a joint American‐​European intervention. Thus, while targeted strikes could delay Iran’s ability to develop nuclear weapons by destroying infrastructure, they would probably incentivize Iran to redouble its enrichment efforts under the conviction that only a nuclear deterrent can ensure its future survival.

This logic also implies broader strategic costs to an attack on Iran: it would exacerbate the problem of nuclear proliferation more generally. As the current Director of National Intelligence Dan Coats recently acknowledged at the Aspen Security Forum, U.S. actions against Saddam Hussein’s Iraq and Muammar Gadhafi’s Libya have made it clear to other states, like North Korea, that a nuclear deterrent may be the best way to ensure regime survival in the context of a war‐​prone United States. 115 North Korea itself confirmed this logic, releasing a statement after a 2016 nuclear test arguing that “the Saddam Hussein regime in Iraq and the Gaddafi regime in Libya could not escape the fate of destruction after … giving up nuclear programs of their own accord.” 116 As Nobel laureate Thomas Schelling has famously pointed out, American nonproliferation policies are ironically a prime driver of nuclear proliferation. 117 If, after successfully negotiating a nuclear deal, the United States then engages in an aggressive war against Iran despite Tehran’s full compliance with the JCPOA, other potential proliferators would have no reason at all to believe that the United States can be trusted to negotiate in good faith.

Conclusion

Though the Trump administration’s Iran policy review appears predestined to produce a more belligerent approach towards Iran, each of the options explored in this paper has significant flaws. Indeed, each option is unlikely to achieve its stated objectives, while at the same time creating an unacceptably high risk of exacerbating the very problems the Trump administration seeks to resolve. At a fundamental level, a more assertive U.S. policy towards Iran—whatever the details—will inevitably intensify Iranian fears about the country’s national security, worsening the very behaviors that the United States seeks to forestall. Even adopting one of these more hostile approaches to Iran while nominally upholding the JCPOA presents greater problems than embracing the nuclear deal and using it as a vehicle for further engagement designed to temper Iranian behavior.

As this paper highlights, it is doubtful that ratcheting up economic sanctions will alter Iranian policies in a more constructive direction, especially in the absence of international cooperation. Likewise, by pushing back harder against Iranian influence throughout the Middle East, the United States would incur substantial long‐​term costs in exchange for negligible gains in regional security. Moreover, a more aggressive approach could lead to unintended military escalation. Supporting internal opposition groups to pressure the regime or foment domestic upheaval is a hopeless strategy, given Iran’s domestic political realities and America’s long history of failed regime change endeavors. Finally, direct military action would have little public support, no legal basis, and most likely produce profoundly negative consequences for regional security and American interests.

Such actions would effectively return U.S.-Iranian relations to the cycle of enmity in which they were trapped prior to the negotiation of the JCPOA, with the nuclear issue dominating as a justification for continued hostility. Indeed, prior to the JCPOA, American allies in the region, particularly Saudi Arabia and Israel, often used the issue of Iran’s nuclear program to steer American policy toward Iran in a more confrontational direction. In private conservations with U.S. officials early in the Obama administration, then‐​king Abdullah bin Abdulaziz al‐​Saud pushed U.S. military action against the Iranian regime. 118 From 2010 to 2012, there were reports that Israel was close to initiating military strikes against Iranian nuclear facilities, knowing it would likely trigger U.S. involvement. Israeli Prime Minister Benjamin Netanyahu’s cabinet officials reportedly blocked him from taking this step. 119

Maintaining and strengthening the JCPOA will help to minimize the future potential for such pressure. Though he fought hard to subvert the JCPOA, for example, Netanyahu has been relatively silent since its adoption. Carmi Gillon, former head of the Israeli security agency Shabak, wrote in July that, thanks to the JCPOA “the threat of an Iranian nuclear weapon is more remote than it has been in decades.” Gillon added, “the majority of my colleagues in the Israeli military and intelligence communities supported the deal once it was reached, [and] many of those who had major reservations now acknowledge that it has had a positive impact on Israel’s security and must be fully maintained by the United States and the other signatory nations.” 120

If the United States is to avoid returning to high levels of tension and conflict in the U.S.-Iranian relationship, it must avoid the more belligerent options explored in this paper. The alternative—the option most likely to produce a positive outcome for all parties—is to uphold the JCPOA, carefully enforce its terms and conditions, and build on it to further engage Iran where its interests overlap with the United States. Pursuing greater diplomacy and engagement with Iran is, ironically, low‐​hanging fruit at this time. Iranian President Hassan Rouhani, who in his first term helped shepherd the JCPOA to fruition, won reelection this year by a wide margin, receiving 57 percent of the vote (compared to 38.5 percent for his chief opponent). 121 The idea of greater engagement with the West was a key component of Rouhani’s electoral platform; both centrists like Rouhani and reformers like former President Mohammed Khatami have argued in favor of what they describe as “JCPOA 2.0,” a series of internal policy compromises that will allow Iran to continue to engage with the West and begin to reintegrate into the global economy. 122

The key to reaping the benefits of a more conciliatory approach is recognizing that Iran is not a unitary actor. Iranian politics, though not fully democratic, are dynamic and competitive, and include various factions, from conservative hardliners to moderate reformists. The nuclear deal is widely popular in Iran, but antagonism from the Trump administration will bolster the prominence of Iranian hardliners who felt Tehran capitulated too much in the negotiations and who use fears of U.S. duplicity to undermine the idea of constructive engagement with Washington. 123 Similarly, perceptions that the United States is failing to live up to its side of the bargain—or is taking new steps that may undermine Iranian security—weaken political support for pragmatic reformists who see value in making concessions to the West in exchange for sanctions relief and integration with the outside world. Ultimately, unlike the more aggressive policy options explored in this paper, further engagement with Iran when possible will strengthen Iran’s more moderate political factions and weaken hardliners, providing a more hopeful future for U.S.-Iranian relations.

Notes