The extension of the deadlines for the ongoing nuclear negotiations between Iran and the P5+1 adds drama to a related standoff in Washington—that between President Barack Obama and Congress—over whether and how a deal should be struck. The Obama administration, eager to reach an accord with Tehran, seems ready to agree to terms that, a few years ago, it called unacceptable. But Congress, suspecting that the president would accept even a bad deal in order to claim a foreign policy victory, is threatening to ratchet up sanctions on Iran before a settlement is reached. During the next negotiating period, this dispute will only escalate. 

Yet the relentless focus on the agreement itself obscures an important truth: much of the struggle to ensure the deal’s success will come after the ink is dry. A host of obstacles could undermine the future agreement’s sustainability, and even the most favorable deal reached by the end of the new extension period would represent the start of the real work rather than a victory. 


The weeks leading up to Monday’s deadline saw surging expectations that a deal would be struck, fueled by what appeared to be an orchestrated series of leaks from the U.S. administration highlighting various potential compromise arrangements. Although Secretary of State John Kerry and his European counterparts ultimately failed to reach an agreement with the Iranian negotiators, their seven-month extension of the Joint Plan of Action gives the parties more time to find a compromise. It also prolongs the bitter dispute between the White House and Congress over whether any terms would be good enough. 

Obama has said that he will not agree to a bad deal, but he is under great pressure to reach some sort of accommodation. Failing to come to terms with Iran would add to his growing list of diplomatic setbacks. That is why many in Congress believe that Obama would approve the bargain even if it falls far short of the original objective: blocking Iran from pursuing any nuclear programs that could give it a weapons capability. Indeed, the administration itself has indicated that it would be willing to settle for a lesser goal: extending Iran’s so-called breakout window—the time that it would take the country to cross the nuclear arsenal threshold—from its current estimated level of two months to up to a year. Obama’s readiness to avoid seeking congressional approval for the agreement, if necessary, only deepens legislators’ suspicions.

To prevent the president from unilaterally signing what they see as a weak deal, senators from both political parties recently reintroduced legislation that would reimpose sanctions on Iran in the case of another extension. The legislation would also require that Congress get a 15-day review period to sign off on any agreement and allow it to cut off funding for implementing the deal, effectively killing it. Although the bill’s sponsors failed to force a vote last week, they have vowed to reintroduce the legislation once Republicans have control of the Senate in January. 


Given the fraught nature of the negotiations and their multiple extensions, the foreign policy discussion has understandably focused on whether an accord with Iran is a realistic possibility. But simply signing the deal would not guarantee its success. Even if the parties do reach a settlement, the process of implementing it would give rise to more significant challenges.

If Congress remains unsatisfied with the agreement’s terms, for example, it could impose additional sanctions on Iran—a move that would probably scuttle the nascent deal. In fact, the severity of today’s sanctions is the result of tough measures Congress began passing in 2010, in response to what it considered an overly conciliatory stance taken by the Obama administration. The White House has tried hard to block those sanctions, mostly unsuccessfully. It then used the possibility of additional retaliatory measures as leverage with Iran to encourage the current round of talks.

Any agreement that merely freezes Iran’s nuclear program, rather than terminating it altogether, would run up against congressional skepticism and resistance. Even Iran’s full and faithful execution of the deal’s terms would not prevent future battles between Congress and the White House. And if Obama manages to suspend current sanctions without congressional approval, Congress could impose new measures that do not give the president waiver authority and therefore cannot be lifted without congressional action. 

Iran, for its part, may not be so likely to cooperate after the deal is struck. Obama administration officials have argued that Iran has honored its obligations under the interim agreement that governs the negotiations, but critics in Congress dismiss such compliance as unimpressive. Instead, they slam the interim agreement for offering significant U.S. concessions on sanctions in exchange for only modest Iranian concessions on nuclear activities. In the aftermath of a settlement, even this current level of Iranian compliance would be far from guaranteed. Given Iran’s long history of secrecy over its nuclear program, a likely scenario would involve significant domestic clashes over the true meaning of the deal’s terms and the extent to which Iran must provide information and access. If the resulting uncertainty leads Obama, Congress, or other P5+1 countries to believe that Iran is defaulting on its obligations, the bargain could fall apart.

Another challenge is the approaching end of Obama’s presidency. The deal is guaranteed its priority status on Washington’s foreign policy agenda only while he’s in office. In two years, a new president could reassess the desirability of a compromise with Iran and request significant revisions to its terms, endangering any agreement reached by that time. After all, Obama himself reworked trade agreements with Colombia and South Korea that had been handed over to him by the outgoing George W. Bush administration. If a Republican contender wins the White House in 2016, the Iranian deal would become a tempting target for critical review.

Even before then, some of the underlying drivers of the settlement, such as the perceived importance of Iran’s support in confronting the Islamic State of Iraq and al-Sham, may shift. If the United States has less need to cooperate with Iran—or if the expected benefits of such cooperation fail to materialize—some of the props reinforcing the deal might collapse.

Further, even though an accord with Iran will ease certain nuclear-related sanctions imposed by the United States and the European Union, it will have no effect on many other sanctions related to Iran’s aid to international terrorist groups and its human rights abuses. Washington has made clear that it will keep up aggressive enforcement actions against companies that violate such remaining sanctions. This continued pressure could deter foreign investors, whom Iran hopes to attract, and could be seen in Tehran as reneging on the spirit, if not the letter, of the agreement. 

Finally, U.S. allies could easily kill the deal through unilateral aggression. If, for example, Israel attacked Iran’s nuclear facilities, as it has repeatedly threatened to do, the agreement would almost certainly disintegrate. 

Even if a bargain is struck by the next deadline, the likelihood that it would weather such challenges over the medium and long term is lower than many believe. As difficult as it would be to reach that milestone, the Obama administration should think of signing the agreement as the starting point on a long road, not the finish line and a foreign policy victory.


But the very precariousness of a future settlement might work in its favor. Because any deal will be vulnerable in its infancy, the Obama administration will have to work diligently to protect it, rallying Congress, its own agencies, and its foreign allies to see the agreement through.

First, the tenuous nature of the deal would give Congress the opportunity to influence the terms of its implementation after it’s signed. For example, if Congress remains unsatisfied with Iran’s willingness to share information or grant international inspectors access to nuclear facilities, it can press the president to be more aggressive by threatening to pass harsher legislation. But Congress should be wary of pushing too hard, since adopting a maximalist position could drive a wedge between the United States and the EU and cause the sanctions regime to collapse in the same way that multilateral sanctions on Iraq collapsed in the late 1990s.

Moreover, just as Congress’ aggressive posture toward Iran served as a necessary complement to the White House’s conciliatory approach, so, too, can the administration leverage congressional pressure to force Iran to honor its commitments. And Obama’s lame-duck status could actually provide an added impetus for the pact’s successful implementation. The only chance for the deal to endure beyond his presidency is if it shows good results over the next two years. This tight time frame will keep the White House committed to making progress.

Success, however, depends on whether Obama and Congress can cooperate, a sight that has become rare in recent years. Since the dramatic midterm elections, Obama has grown eager to pursue portions of his agenda that do not depend on Congress. When it comes to Iran, however, he may not have that option—not if he wants this agreement to last beyond the signing ceremony.

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