Could a Republican President Undo an Iran Deal?

U.S. Secretary of State John Kerry meets with foreign ministers of Germany, France, China, Britain, Russia and the European Union during the Iran Talks meetings at a hotel in Vienna oin July 7, 2015. Carlos Barria/Reuters

If the United States reaches a nuclear deal with Iran, as negotiators are scrambling to do this week (the deadline has been extended until Friday), the outcry from Republicans on the 2016 campaign trail is likely to be fierce. Some have already promised to undo any agreement reached with Iran, or at least roll it back significantly. "On January 20, 2017, if I were elected president I would pull back from this awful deal on the very first day," Wisconsin Gov. Scott Walker told radio host Lars Larson last week. In reality, that's highly unlikely.

Experts on the region and nuclear pacts say unraveling any deal once it goes into force will be fraught with diplomatic, financial and security risks that will make it all but impossible for a Republican president to just scrap it right off the bat. Former Florida Gov. Jeb Bush hinted as much in an op-ed on the conservative web site, though unlike Walker, he did not come out and say he'd rip an agreement on Day One. "Undoing the damage done by a fundamentally flawed nuclear deal will not be easy," wrote Bush. But he insisted doing so is "essential for the security of the United States." It's more likely, however, that moves by Tehran—not Washington, D.C.—will either propel the nuclear deal forward or put it in jeopardy.

Iran has a history of testing the limits of its international agreements, particularly when it comes to its nuclear program, points out Ambassador Dennis Ross, counselor at the Washington Institute for Near East Policy. Tensions over implementing the new deal, including different interpretations of the limitations, are inevitable. But "a lot depends on when they test the limits and in what ways they test the limits," Ross says. He says if the Iranians are smart, they won't try and test Washington until after some time into a new administration is in power. At that point, it would be up to the new administration how forcefully to push back.

"If we get an agreement that's actually successfully implemented for a year and a half [under Obama], I don't think any Republican president would cut up a deal," says Ilan Goldenberg, director of the Middle East Security Program at the Center for a New American Security, a D.C. think tank. That, Goldenberg notes, would shatter the international consensus reached among the group known as the P5+1, which includes permanent United Nations Security Council members the U.S., France, the United Kingdom, Russia and China, as well as Germany. It would also roil a region already in flames and up the prospects for Iranian reprisals. And it could harm international energy markets, which are eager to get their hands on Iran's significant oil reserves, if and when Western sanctions against the country are lifted under the prospective deal.

"I don't think Iran is going to walk away from this quickly," says Goldenberg, previously a senior Middle East policy adviser at the State Department and Pentagon. "I think they'll implement the agreement," at least in the early stages. That would likely force the next administration to hold up its side of the bargain, as well, at least initially. "I can see a Republican administration coming in and holding their nose and implementing it," Goldenberg says. "But not vigorously implementing it."

The questions are more likely to come in the ensuing years, as the politics shift and new challenges emerge.

Implementing any nuclear deal, with its reams of technical annexes, requirements for inspections and limits on certain types of scientific research and trade, is always a complex affair, with plenty of gray areas not outlined explicitly in the text of the agreement. Experts agree carrying out a deal with Iran will be at least as challenging as negotiating it.

In addition, there's a whole other dynamic to U.S.-Iran relations that America's new leader will have to contend with: Iran's support for terrorism. That's not addressed in the nuclear negotiations but it's likely to play into tensions over its implementation.

"Let's say you're buying 10 to 15 years," with this deal, says Ross, who was a senior advisor in the George H.W. Bush, Bill Clinton and Barack Obama administrations. "Well what do you do with those 10 to 15 years?"

Israel and the Saudis will "want to see what more we're doing to enhance our deterrence" against Iran, and whether we "raise the costs of what the Iranians do in the region," he says. If the Iranians are unhappy with how the nuclear deal is playing out, they may well lash out. But Ross thinks it's more likely they would do so in ways that doesn't risk the agreement, fomenting proxy attacks on U.S. allies, for example, rather than violating the rules on nuclear enrichment or building centrifuges. Those types of things wouldn't necessarily scuttle the agreement. But they could, depending on the strategies and responses of the next American president.

And that's where some of the tough talk on the 2016 campaign trail could come into play. Goldenberg predicts that "there will be violations, there will be reasons for contention. How you handle those moments is key."

He adds: "You can see that going very differently if you had someone" in the White House "who's not very interested in implementing the deal."