Iranians are gathering today for picnics to mark sizdah bedar, the culmination of the annual celebration of the Persian new year (Nowruz.) Nowruz, a pre-Islamic holiday that coincides with the spring equinox, remains “so embedded in Persian culture” that it endured the early puritanism of Iran’s post-revolutionary era. For millions of Iranians and others who celebrate, the weeks around Nowruz mark an annual opportunity for ritual and renewal, a time for housecleaning and family get-togethers, casting out the dark winter and welcoming the fresh buds of spring.

For Iran’s leadership, the advent of a new year comes at a time of historic uncertainty, both at home and across the regional and international horizon. The street protests that erupted unexpectedly in late December and convulsed 80 cities across Iran have mostly abated now, but frustration over economic conditions and social and political restrictions continues to smolder. That unrest has left Tehran’s political class feeling unusually on edge, sharpened by new provocations from former President Mahmoud Ahmadinejad and the intensifying jockeying around a future succession process for Iran’s supreme leader.

Meanwhile, having beaten back the Islamic State in Iraq and opponents of Bashar Assad in Syria, Tehran now faces powerful resistance to its expanded regional posture—from Israel, which has launched attacks on Iranian positions in Syria, and from its traditional rival Saudi Arabia, whose brash young crown prince appears determined to contest Iran’s reach at any price. Across a tense and unsettled region, Iran remains the 800-pound gorilla, but Iranian commanders are wary about the prospect of new pushback, promising that “we won’t be blindsided by the enemies.”

Dark clouds in DC

The most imminent threat, however, emanates from Washington, where the Trump administration is poised to upend the 2015 nuclear deal, a move that would reinstate harsh economic sanctions on Iran and intensify frictions between the two old adversaries.

Last week’s announcement that former Bush administration official John Bolton will join the White House on April 9 as Trump’s third national security advisor casts an even more ominous pall over the start of the new year for Tehran. Bolton has consistently and vociferously campaigned against the nuclear deal (the Joint Comprehensive Plan of Action, or JCPOA), insisting that “Trump can and should free America from this execrable deal at the earliest opportunity” and outlining a step-by-step plan for doing so. He proposes to replace diplomacy with military strikes to destroy Iran’s nuclear infrastructure, coupled with “vigorous support for Iran’s opposition, aimed at regime change in Tehran.” Even more unfortunately, Bolton has depicted a deranged, discredited cult of Iranian expatriates as a legitimate opposition movement—a ludicrous embrace that defies explanation, except perhaps the group’s lavish kickbacks.

With Bolton managing the interagency decisionmaking process—and another opponent of the agreement, Mike Pompeo, taking the helm at the State Department—Iranians and the world are already beginning to brace for America’s retreat from the Iran nuclear deal. The appointments added a note of fatalism to an already fitful dialogue between Washington and Europe, aimed at heading off President Trump’s ultimatum to address the agreement’s perceived shortcomings before the May 12 deadline for extending U.S. sanctions waivers on Iran. Related Content Iran Is Trump stuck with an Iran deal he loathes? Markaz “Fix” the Iran deal, but don’t move the goalposts Play Video Unpacked To help Iran’s protestors, keep the nuclear deal intact

The prospective upending of the nuclear deal has already incited a torrent of outraged op-eds and well-meaning expert appeals for a reprieve. The outcry seems unlikely to sway the dealmaker-in-chief, whose loathing of the deal has been one of the few constants in his erratic foreign policy vision since the 2016 campaign. The lurch toward a more intransigent U.S. national security team only compounds the challenge for America’s partners in the deal—Britain, France, and Germany—whose diplomats have been frantically trying to devise a supplemental pact that meets Trump’s demands while avoiding an explicit violation of the existing nuclear agreement.

If the European effort fails—and it is a fair bet that it will—Trump has pledged to “terminate” the agreement in May. The fallout for Iran could be severe: As the full suite of American sanctions, including penalties on importing Iranian crude oil, snap back into place, Iran’s precarious economic situation will certainly deteriorate. Over time, depending how adeptly the regime harnesses the inevitable nationalist backlash, the sanctions will intensify the simmering dissatisfaction on the streets and among the political elite. Iran’s long experience with sanctions and international recrimination means that pressure tends to play out in an unpredictable fashion. For now, it’s anyone’s guess whether the breaking point comes in the form of a negotiated resolution, as it did in 2013, or via some more catastrophic outcome.

Washington must recognize that the costs of American abrogation of the nuclear deal will not be borne by Iran alone.

But however the next step goes down in Iran, Washington must recognize that the costs of American abrogation of the nuclear deal will not be borne by Iran alone. Terminating the JCPOA will corrode any prospect of sustaining Iranian compliance with the deal’s constraints on its nuclear program as well as the transparency provided via the deal’s rigorous inspection regime. The collapse of the deal will reverberate across the landscape of American interests and influence: generating a trans-Atlantic rift at least as acrimonious as that incited by the 2003 Iraq war, undermining multilateral diplomacy around other urgent crises—such as North Korea—and bolstering Russian and Chinese influence in the Middle East. Many project that the end of the nuclear deal would launch an inexorable march toward a direct military conflict with Iran, with ruinous consequences for regional stability and the global economy.

Bring it on, say the deal’s fiercest critics, who contend that the most perilous forecasts mostly reflect partisan fear-mongering and that contingency planning can mitigate any worst-case scenario. In October 2017, Bolton disdained any “too-cute-by-half approach” that seeks to improve the nuclear deal, and he has argued instead for a maximalist approach, including military strikes, intended to remove the Iranian government. Bolton’s dogmatic stance exceeds the Republican mainstream, but his diagnosis has wider currency, especially among U.S. allies in the region, who maintain that drastic measures offer the only possible pathway for overturning Iran’s creeping dominance across the Arab world.

Related Books Upcoming Iran Reconsidered

Here at Brookings, we have been engaged in a conversation with both sides of the newly reanimated Iran debate, and leading up to the May 12 deadline on next steps for the nuclear deal, keep an eye out as we examine the arguments around what Washington should do about the agreement and about Iran more broadly, as well as implications of those steps.