When the administration of U.S. President Donald Trump ratcheted up its “maximum pressure” campaign last May, with the professed aim of driving Iran’s oil exports to zero, it didn’t take long for Tehran to respond with escalation of its own. In the months since, Iran has reportedly attacked pipelines, tankers, and one of the world’s largest oil processing facilities in Saudi Arabia—prompting a spike not just in oil prices but also in worries about a new war in the Middle East. It has also repeatedly breached the original terms of the 2015 nuclear accord—known as the Joint Comprehensive Plan of Action, or JCPOA—which sought to limit the country’s nuclear activities and from which the Trump administration withdrew in 2018.

Tehran likely intended these moves to persuade the United States to reconsider its sanctions campaign, and to spur other parties to the JCPOA to urge Washington to relent. For a while, Iran may have felt its approach was working: French President Emmanuel Macron and British Prime Minister Boris Johnson both tried to engineer a deal in which Iran would return to compliance with the JCPOA in exchange for sanctions relief. Such a bargain was reportedly derailed at the last minute in September, when Iran demanded that sanctions relief precede a proposed meeting between Trump and Iranian president Hassan Rouhani at the U.N. General Assembly. But since then, Iran may have overstepped. On November 9, it announced plans to resume uranium enrichment at an underground bunker and to ramp up the pace of enrichment elsewhere. In response, European signatories to the JCPOA threatened to reimpose sanctions.

With Iran testing the limits of European patience, the United States has an opportunity to forge a united front with its erstwhile European partners and push Iran to return to the negotiating table. Together, they should offer a straightforward proposition: engage constructively, and some sanctions will be suspended while a new deal is negotiated. Continue to expand nuclear activities and refuse new negotiations aimed at strengthening the JCPOA, and Europe will join the United States in reimposing the sanctions lifted under the deal.

INCREMENTAL ESCALATION

For the first year after the United States disavowed the JCPOA, Iran appeared content to wait out the Trump administration. In response to escalating U.S. pressure, it attempted to cajole European countries into defying American secondary sanctions, which penalized foreign firms for doing business with Iranian banks but for a time permitted the sale of Iranian oil. Once the United States got serious about eliminating Iranian oil exports entirely, however, Iran changed its strategy.

Over the last six months, Tehran has taken four incremental steps to expand its nuclear activities, each designed to breach one or more of the JCPOA’s original terms. On May 8, Iran announced that it would no longer honor the deal’s limit on stockpiles of low-enriched uranium. Then on July 7, Iranian officials indicated that they would enrich uranium to 4.5 percent, exceeding the 3.67 percent limit specified in the deal. On September 6, Iranian officials indicated that they would accelerate their research and development of advanced centrifuges, which could eventually enable Iran to enrich uranium faster and with fewer centrifuges—and thus in smaller, more easily concealed facilities—than it currently does. And finally, on November 9, Iran announced that it had resumed enriching uranium at its underground Fordow site.

Initially, Iran’s actions appeared designed to preserve rather than undermine the JCPOA. Iran’s first three escalations were not only reversible but arguably restrained, resulting in a reduction in its “breakout time”—the time required to produce one weapon’s worth of highly enriched uranium—of only about two weeks, according to the Institute for Science and International Security.

Iran’s most recent nuclear escalation set off more alarm bells.

But Iran’s most recent nuclear escalation set off more alarm bells. The Fordow enrichment site is controversial because it was designed to avoid detection and attack. A few days after Iran announced that it would resume enrichment there, an Iranian official confirmed that Tehran had abandoned its JCPOA pledge to convert the facility into a physics research center. The official also threatened that Iran might halt its efforts to reduce the proliferation risks posed by its heavy water nuclear reactor at Arak. Information released by the International Atomic Energy Agency (IAEA), moreover, suggests that Iran’s rate of uranium enrichment—previously above the limit specified in the JCPOA but well below Iran’s capacity—has increased, reducing Iran’s estimated breakout time from 8–12 months to 6–10 months, again according to the Institute for Science and International Security.

Still, Iran’s actions seem designed not to actually produce a nuclear weapon at this stage but rather to get the attention of the United States and Europe. Tehran seeks to push the former to ease up on its maximum pressure sanctions campaign, and to enlist the latter to underscore its message to Washington. In a sense, this amounts to creating a crisis in order to extract concessions for merely returning to the status quo ante—a gambit that North Korea’s government would surely recognize.

Tehran’s approach suggests that it sees the JCPOA as serving its interests and therefore worth preserving. What it does not suggest is that Tehran is committed to nuclear restraint or transparency. Over the past two years, Israeli intelligence operatives have exposed an “archive” of Iranian nuclear weapons research as well as an undeclared facility at Turquzabad in which Iran allegedly stored nuclear material. Neither site was known to the IAEA. In contrast to its loudly trumpeted incremental violations of the original JCPOA terms, Iran not only refused to acknowledge these activities but reportedly sought to conceal them once Israel revealed their existence. IAEA monitoring reports hint that Iran’s cooperation with the agency’s investigation of the matter has been less than satisfactory.

TESTING THE LIMITS

European parties to the JCPOA—the EU and the so-called E3 of France, Germany, and the United Kingdom—have done little in response to Iran’s repeated provocations except condemn them. This is in part because they blame the United States for triggering the crisis by withdrawing from the JCPOA, and in part because they hoped to save the deal and feared that punishing Iran would only prompt the country to escalate further. But this calculus may be changing. In the wake of Iran’s latest nuclear escalation, the EU warned that further provocations could trigger the JCPOA’s “dispute resolution mechanism”—the first step in a process that could culminate in the reimposition of sanctions.

Despite such warnings, Iran is unlikely to shift course, since its objective is to change U.S. policy. Rather, it is likely to continue to dial up pressure on Washington with its strategy of gradual escalation, at least until it is clear whether Trump will serve a second term. If Trump wins reelection, and Iran ultimately resigns itself to a new negotiation with his administration, Iran may escalate far more dramatically—perhaps restoring its nuclear program to pre-JCPOA levels in order to create a sense of urgency and gain leverage in advance of talks.

Nevertheless, growing European impatience with Iran presents an opportunity for the United States. The Trump administration has brought significant economic pressure to bear on Iran: the IMF projects that the Iranian economy will contract by 9.5 percent in 2019. But it has done comparatively little to build up diplomatic pressure. On the contrary, it has eagerly sought a summit between Trump and Rouhani that is unlikely to materialize but gives Iran a carrot to dangle.

In the wake of Iran’s latest nuclear announcement, the United States should attempt to form a common diplomatic front with its European partners and rally additional support from partners in Asia and elsewhere. Together, they should offer Iran new nuclear and missile talks, beginning not with a summit but with discussions among lower-level envoys. They should offer to temporarily freeze some sanctions if Iran constructively engages and halts its nuclear escalation, and threaten to ratchet them up if Tehran refuses. Such an approach would offer the clearest path to the new agreement the Trump administration desires. It would also begin to heal a rift between the United States and its allies that Iran has exploited and that has distracted from greater strategic priorities such as Russia and China.

Iran is likely to continue to dial up pressure on Washington with its strategy of gradual escalation, at least until it is clear whether Trump will serve a second term.

Should new negotiations materialize, the United States and Europe should approach them with the lessons of the last two years. Iran’s old-model centrifuges and declared enrichment facilities, it has become clear, are largely sticks with which to rattle the West; were Iran to try to actually use them to break out and produce a nuclear weapon, the risk of being caught—and presumably attacked—would be high. To actually produce a nuclear weapon, Iran would need to do so clandestinely, which would require using more advanced centrifuges, barring inspections at the sites involved, advancing its missile technology, and keeping its weaponization activities off-limits entirely. The revelations of the last two years suggest that Iran has laid the groundwork for such a clandestine program while at the same time opening up its declared nuclear program to inspections. Any new deal should be designed to detect and prevent a clandestine program.

Trump withdrew from the JCPOA in the hope of securing a bigger, better deal with Iran. Yet despite overwhelming economic pressure, no new negotiation has materialized. Iran’s repeated provocations give the Trump administration an opportunity to ramp up diplomatic pressure as well, and to rally European support for a new round of talks. If his administration doesn’t seize this opportunity, Trump will end his first term not with stronger nuclear constraints on Iran but with Iran expanding its nuclear activities and shortening its breakout timeline in the face of fragmented international opposition.