U.S. President Donald Trump denounces the Iran Deal in the Diplomatic Room of the White House, Washington, D.C., October 13, 2017.
Kevin Lamarque / Reuters

On Friday, the United States reached a turning point in its relations with Iran. U.S. President Donald Trump forcefully denounced the Islamic Republic in a highly confrontational speech, threatening to upend the nuclear deal unless Congress amends it to make its terms more restrictive. By refusing to certify the accord, despite verification that Iran is in compliance, Trump essentially torpedoed the hard work that led to Washington’s recent opening to Tehran. His brash move, coupled with other escalatory measures—the designation of an entire branch of Iran’s military, the Islamic Revolutionary Guards (IRGC), as a sponsor of terrorism, as well as the Trump administration’s hostile attitude and stark absence of diplomacy—will likely not only jeopardize the nuclear deal and U.S. credibility among key allies, but also put the United States on a path of escalation with Iran. This is all the more problematic given that the United States has failed to maintain meaningful channels of communication with Iran and that its dangerous policy shift effectively undermines diplomatic measures going forward. 


One of the main risks of decertifying the nuclear accord (known formally as the JCPOA) is that the United States could face increased isolation and a loss of credibility among its international partners. China, France, Germany, Russia, the European Union, and the United Kingdom are all parties to the deal as well. In the lead-up to the nuclear talks, these countries and other international partners, including the likes of India, Japan, and South Korea, complied with U.S. secondary sanctions on Iran at major expense to their own domestic economies. They made their decision believing that the United States had a clear and viable strategic vision to constrain Iran’s nuclear program, including a credible commitment to diplomacy. Washington will thus face an uphill battle in securing international buy-in to support its current move. And without a united front, Iran’s position will be strengthened. What’s more, should Tehran eventually lose its incentive to fully comply with the JCPOA, it will be able to blame the United States. 

Trump’s decision could also trigger internal changes within Iran that could hurt U.S. interests. Tehran’s near-term response might be limited to taking reciprocal action in its Parliament, launching a complaint with the JCPOA Joint Commission, and testing the limits of its nuclear obligations; Rouhani administration officials have signaled that they will adopt a “wait and see” approach. But the decertification will most certainly affect the long-standing internal debates between Iran’s more moderate and hardline factions about whether to engage with the United States. This is particularly significant because constraining Iran is not just about curbing its technical abilities but also about securing its cooperation. As the U.S. intelligence community has long asserted, “Iran does not face any insurmountable technical barriers to producing a nuclear weapon, making Iran’s political will the central issue.” Accordingly, moderate voices who advocate for continued nuclear constraint will find it increasingly difficult to defend their position, especially as the narrative of Iran's Supreme Leader Ali Khamenei and other hardliners gains traction. They have argued that the United States has only hostile intentions toward Iran despite the compromises Tehran has made.

Trump may very well be handing Khamenei a golden opportunity to demonstrate to both members of the Iranian political elite and the Iranian people (who have largely been supportive of engagement) that the United States simply cannot be trusted. When coupled with other measures—particularly those that strike a sensitive chord among the Iranian people, such as visa restrictions indefinitely banning most of them from traveling to the United States, hostile rhetoric broadly labeling Iran a “terrorist nation like few others,” calling the Persian Gulf the “Arabian Gulf,” and ramping up sanctions—Khamenei’s message may increasingly resonate inside Iran. That would represent a major strategic loss to the United States. 


To add fuel to the fire, Trump designated the entire IRGC as a sponsor of terrorism on Friday. Although Washington must find an effective way to address IRGC activities that run counter to U.S. interests, the designation may not be the right approach. First, it largely duplicates current sanctions against the IRGC for its involvement in Iran’s ballistic missile program and for human rights abuses. Second, even though the designation stops short of labeling the IRGC a “Foreign Terrorist Organization,” the context—Trump’s hostile rhetoric and the policy shift—makes the move more likely to trigger a retaliatory response. IRGC commander Mohammad Ali Jafari recently stated that if Washington moved forward with the designation, “the IRGC [would] consider the U.S. armed forces equivalent to the Islamic State, all over the world and especially in the Middle East.”

Although the IRGC remains one of the most heavily sanctioned entities in the world, it has nevertheless historically been able to expand its role in the Iranian economy. Still, the designation may have a chilling effect on companies conducting legitimate business with non-sanctioned entities in Iran. This would undercut the United States’ ability to incentivize Iran to continue to comply with the JCPOA or otherwise exercise restraint.

Politically, the policy could boost the image of the IRGC in Iran. Regular IRGC forces number in the hundreds of thousands and its paramilitary and mass-movement wing, the Basij, number in the millions. The IRGC’s widespread presence in Iranian society will leave President Hassan Rouhani little choice but to publicly rally behind it. Indeed, the various political factions in Iran have already publicly demonstrated their united support for the Guards and Rouhani has lauded them for their defense of Iran’s “national interests,” such as fighting the Islamic State (ISIS) in Iraq and Syria. Rouhani also noted that the IRGC has a special place “in the hearts of Iranian people.” This stands in stark contrast to Rouhani’s recent criticisms of the IRGC, in which he said that it had outsized influence over the economy and needed to step back. Washington’s designation could disrupt Rouhani’s agenda to limit the Guards’ role in the economy. 

In Iraq and Syria, where U.S. military personnel serve in proximity to IRGC forces, Trump’s policy could muddy and complicate the rules of engagement on the ground. Iran will likely avoid situations that bring it into direct conflict with the United States, but there is still significant potential for miscalculation to lead to direct or proxy fighting between the two sides. Furthermore, Trump’s decision could hurt Iraq, since Iranian-backed forces, including the Popular Mobilization Forces, remain at the forefront of Baghdad’s ground offensive against ISIS. The decision could potentially have destabilizing political consequences for Iraq should Iran choose to use its influence there to pursue more hostile policies. More generally, the IRGC designation will further fuel popular conspiracy theories across the Middle East that the United States is colluding with ISIS, since many in the region consider the Guards to be the leading force in the fight against the terrorist group. 


Much as former President George W. Bush’s 2002 “axis of evil” speech marked a negative turning point in limited U.S.-Iranian outreach and cooperation 15 years ago, Trump’s stark policy shift will do similar damage. Back then, Bush’s speech came on the heels of meaningful U.S.-Iranian cooperation on Afghanistan under the leadership of former reformist Iranian President Mohammad Khatami, who famously called for a “dialogue among civilizations.” Bush’s speech, however, along with an array of complex factors, ultimately weakened Khatami and his reformist allies who advocated for increased dialogue with the West. This helped strengthen the hand of hardline elements advocating for continued resistance to the United States and Europe. In the decade that followed, Iran vastly expanded its nuclear program and increased its regional influence—neither of which was beneficial to U.S. interests. Similarly, today’s shift comes after an unprecedented level of engagement between Iran and the United States, as well as a greatly expanded level of cooperation between Iran and the international community on its nuclear program. These recent developments have taken place under the leadership of Rouhani, who has now largely inherited Khatami’s reformist constituents. His platform has centered on moderation and dialogue. Thus, Trump’s latest provocations will likely deal yet another blow to Iranian moderates.

As it has for decades, Iran continues to pose serious challenges to U.S. interests, whether through its militant activities in the Middle East, its ballistic missile development, or its detention of dual U.S.-Iranian nationals. Yet Iran is now a significantly more powerful regional actor, having expanded its influence across Iraq, Lebanon, Syria, and Yemen. If we lose the JCPOA, we might be facing a nuclear crisis in the Middle East. That is why the need for an effective strategy to both counter and engage Iran and bind it to a rules-based international order is much greater than ever before. The current period of escalation is fraught with risk and makes the implications of miscalculation that much more consequential.


Correction Appended (October 17, 2017): An earlier version of this article noted that the IRGC terrorist designation "is not the right approach." It is more accurate to say that the designation "may not be the right approach," and the sentence has thus been amended accordingly.

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  • PAYAM MOHSENI is Director of the Iran Project and Fellow for Iran Studies at the Harvard Kennedy School Belfer Center for Science and International Affairs.
  • SAHAR NOWROUZZADEH is a Joint Research Fellow at the Iran Project and the Project on Managing the Atom at the Harvard Kennedy School Belfer Center for Science and International Affairs. 
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