Kevin Lamarque / Reuters

Congress and the body politic are appropriately consumed with the Iran nuclear deal. Was it a good one or a bad one? Will it lead more rapidly to a nuclear-armed Iran, as several Republican presidential candidates have said, or postpone that prospect for perhaps 10 to 20 years, as the administration says? Will it be accepted by Congress? These are the kinds of questions dominating news debates and web discussions. I am watching and reading carefully, trying to weigh pros and cons. I have found especially helpful the tough-minded but fair critique of Dennis Ross and the terrific dialogue among three of The Atlantic’s finest, Peter Beinart, Jeffrey Goldberg, and David Frum.

There is another question, though, that has not been asked much. My friend Robert Satloff, as savvy a Middle-East analyst as exists, has a fascinating piece in Politico on the consequences if the Iran deal fails in Congress. Satloff dismisses in firm and almost peremptory fashion the president’s contention that it would lead inexorably to war. He suggests one possibility is that the president would go back to the bargaining table to try to craft a better deal. I think the possibility of that happening is zero. First, most members of Congress who rejected the deal on the table would reject any deal put forward by Barack Obama. If somehow in the unlikely—make it almost impossible—scenario that Obama could convince his partners to go back to the table, and convince Iran to do so, and get more concessions from Iran, congressional Republicans would say, “Great—now go back to the table again; if they agreed to more this time, you can get more yet!”

So if Congress does override a presidential veto, there would be no new deal, but several other consequences would flow. Satloff notes, correctly, that a rejection by Congress does not mean the whole deal is blown up. The deal, remember, is between Iran and the P5+1, and is likely soon to be ratified by the United Nations Security Council. And, as Satloff says, after a veto override in September, ratifying Congress’s refusal to let the president waive sanctions against Iran, the president would likely use his executive authority to tell the Treasury and State Departments to turn their enforcement powers elsewhere, leading to a congressional lawsuit and a series of battles in federal courts.

If that happens, it would not surprise me to see Republican congressional leaders go judge-shopping, as happened in the case of his immigration executive orders, finding a conservative judge who would quickly put an injunction on the president’s actions, in a circuit, like the Fifth, that is dominated by like-minded jurists. But in any case, it would be some time before the timetable for sanctions relief took hold. In the meantime, almost certainly, the other nations in the P5+1 would hold to the deal, as would Iran, even if ultimately American sanctions were not waived. The money that Iran would get, including from enhanced trade with Russia, China, Europe and a host of other countries that have imposed sanctions at our request or command but would drop them summarily, would still make the deal worth its while.

Two other things would make the deal especially worth Iran’s while. First, as Satloff points out, the rebuff by Congress would drive a deep wedge between the U.S. and its partners in the deal, including our European allies. Every time the administration worked on another deal with them, they would no doubt ask whether the U.S. could keep its word if the White House and the executive branch no longer controlled American diplomacy. And, of course, Russia and China would gleefully jump on the evidence of a lack of U.S. credibility and a deepening of our obvious political dysfunctionality.

Second, an override by Congress of the deal would be attributed by our allies and many others to the fierce lobbying campaign by Israel—and it would give European countries even less reason to act against the aggressive efforts in their own countries and in the U.N. to isolate Israel and treat it as a pariah state, and more reason to pile on. These efforts are outrageous, hypocritical and dangerous, but the widespread sense that Israel blew up the American role in the deal would give them even more rationalization in too many quarters in the world.

Of course, it is a reality that a wide array of Israeli lawmakers and officials of all political stripes view the deal with alarm—I have not seen another issue that has such broad consensus, making this issue less easy to characterize as a fit of pique by Bibi Netanyahu. The Israelis and their allies will make their views widely known in Congress. My guess is that, despite their efforts, the persuasive powers of Joe Biden and Ernest Moniz will be enough to keep at least 150 House Democrats on board, meaning a veto override fails. But it is no sure thing.

Count me among those who understand and are uneasy about these consequences and still fear the reverberations of a deal, especially on Iran’s ability to use its resources to bolster Hamas, Hezbollah and Assad and to foment terror in the rest of the region. Lawmakers in the same space should think about a Plan B. And that Plan B should be to condition any vote to sustain a presidential veto on clear commitments from the administration to deal with the real—not faux or overblown—concerns about the deal.

What would such a commitment include? Here is the laundry list: It would start with a guarantee of an aggressive ramp-up of American resources—money, sophisticated weapons and equipment—to help Israel and possibly our Sunni allies, to make sure that the conventional consequences of the deal do not overwhelm the pluses of a considerable delay in Iran’s nuclear capacity. In addition, there should be a guarantee of tough additional sanctions against Iran for bad behavior outside of the nuclear realm as a result of having more resources to give Hezbollah and other malevolent actors; an outline of sanctions and penalties that the United States will seek to get its P5+1 partners to agree will be imposed if Iran cheats at all, including along the margins; and a commitment to use every avenue, including force, if Iran violates the basics of the deal and moves toward a nuclear weapon.

There would be deleterious consequences if somehow Congress undercut the administration and blocked the key portions of a multilateral deal. But there are ways to avoid those consequences and ensure that the positive results outweigh the negative without going back to a mythical drawing board.

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