Today negotiators from Iran, the U.S., and other major powers announced the framework for a deal to curb Iran’s nuclear program, laying the groundwork to draft a final agreement by the end of June. The preliminary deal would limit continued operation of centrifuges to one site, while converting a second one — which had been the subject of controversy — to a research facility. The Arak nuclear reactor could no longer be used to produce weapons-grade plutonium.

In exchange, sanctions against Iran will be lifted by the U.S. and European countries, after the International Atomic Energy Agency verifies Iran has taken those steps. It’s anyone’s guess whether a final deal will be reached, and in the interim, plenty of hard questions will be asked about it.

The 2016 GOP presidential hopefuls are all but certain to oppose the emerging framework, and Congressional Republicans (with the help of some Democrats) will probably try to scuttle any deal before it is signed. But staking out a position against the deal — and trying to sink it — could prove a bit more complicated than it appears.

This is driven home by a new interview that Scott Walker gave to a Wisconsin radio personality, in which he said that not only would he undo any deal with Iran on his first day as president; he would do so even if our European allies wanted the deal to continue.

Walker had previously said that he would undo any deal with Iran on his first day. But radio host Charlie Sykes asked him a good follow-up question, and this happened:

SYKES: You have said that you would cancel any Iranian deal the Obama administration makes. Now would you cancel that even if our trading partners did not want to reimpose the sanctions?
WALKER: Absolutely. If I ultimately choose to run, and if I’m honored to be elected by the people of this country, I will pull back on that on January 20, 2017, because the last thing — not just for the region but for this world — we need is a nuclear-armed Iran. It leaves not only problems for Israel, because they want to annihilate Israel, it leaves the problems in the sense that the Saudis, the Jordanians and others are gonna want to have access to their own nuclear weapons…

In this scenario, of course, the European countries would still see continuing the deal as the best way to prevent a nuclear-armed Iran. But that wouldn’t matter — Walker would pull the U.S. out of the deal, anyway. I asked Peter Juul, a Mideast analyst for the Center for American Progress, to explain what the consequences of that might be. He told me:

“The big questions would be, How would Europeans and Iranians react? It’s hard to believe that the Iranians would stick to their end of the deal. That would leave Iran open to take their nuclear program as far as they want.
“The Europeans would probably try to keep their portion of the deal in place and try to salvage it. This would place the burden of having blown up the deal on us. This would be particularly ironic, considering that a major Republican and conservative talking point is that the Obama administration is breaking faith with our allies. We would be alienating and breaking faith with our European allies right out of the gate. You’d be irreparably damaging our transatlantic relationships for however long Scott Walker were in office.
“Putin is not going to leave power anytime soon, unless he keels over. For all the talk about the Russian threat, it would be odd to throw our European allies under the bus on Iran at the same time they are facing down a Russia that is not particularly friendly.
“There would be a lot of ripple effects around wherever the U.S. and Europe have security cooperation. This is a reckless, irresponsible, shoot first, don’t-ask-questions-ever approach. It’s just not a viable strategy if your goal is to keep Iran from getting a nuclear bomb.”

This all gets at the complexity of the politics of Iran nukes. The pledge to undo any Obama nuclear deal with Iran is already emerging as a key litmus test for the 2016 GOP contenders. But they are essentially framing the question as a narrow one: Will I stick it to Obama and undo his capitulation to Iran on Day One? You’re damn right I will! But in the real world, a deal would involve not just Obama, but our major European allies, and undoing it could unleash all sorts of international complications.

This also should theoretically complicate Congress’ approach to the emerging framework. Right now, Congress is considering two possible votes that the White House fears could scuttle a deal before it is finalized: One that would reimpose sanctions; and a second that would establish a framework for Congressional oversight over a deal that isn’t actually necessary to supply that oversight and could do more harm than good. This latter bill is also supported by a number of Senate Democrats. If Congress does kill a deal, that, too, would end up “placing the burden of having blown up the deal on us” in the eyes of our allies, as Juul puts it above.

All of this should theoretically lead to at least some kind of pressure on members of Congress who are looking to kill a deal — not to mention the 2016 GOP hopefuls — to say what they support doing instead beyond thwarting Obama. “The bottom line is that it’s unclear what Walker and others who think like him want out of this process,” Juul says. “If no deal could possibly satisfy them, they should say so.”