Two presidents of the United States have repeatedly certified that Iran is complying with the terms of the Joint Comprehensive Plan of Action, otherwise known as the Iran nuclear deal. The secretary of state has said that Iran is in compliance. The secretary of defense has argued the agreement merits sustaining. The International Atomic Energy Agency has certified that Iran is in compliance. America’s European allies, who are also signatories to the deal, are united in supporting its continuation.  

And yet, President Trump is telegraphing his intent to decertify the agreement on October 15th. National Security Adviser H.R. McMaster has repeatedly charged that the deal has “fundamental flaws” and that Iran is in violation of “the spirit of the agreement.” Ambassador to the UN Nikki Haley argues that technical compliance by Iran is insufficient. Secretary of State Rex Tillerson is now arguing the deal will need to be renegotiated for the U.S. to remain party to it. But walking away from the JPCOA would be a terrible blunder.

There is no such thing as “the spirit of the agreement.” The nuclear agreement limits Iran’s nuclear weapons programs and nothing else. Things not covered by the agreement include: ballistic missiles; being a state sponsor of terrorism; arming Hezbollah and Hamas; harassing shipping in the Straits of Hormuz; destabilizing regional governments (as Iran is doing in Lebanon, Bahrain, Yemen and elsewhere); being the army keeping Bashar al-Assad in power in Syria; kidnapping foreign nationals; and being a repressive government. The nuclear deal is no help at all in dealing with all those problems, which Iran is causing.

But the nuclear deal takes a potential Iranian nuclear weapon out of the equation for another eight years or more, buying us valuable time to push back on such behavior by Iran—and that is the material advantage of the JPCOA. Taking the development of nuclear weapons off the table for several years removes Iran’s ability to attack the United States while the U.S. and its allies work to reduce Iran’s regional influence and force their compliance with internationally accepted norms of behavior, like respecting the rights of shipping in international waters. The United States has the means, and the international support, to move against Iran in all these areas—as long as America continues to be party to the JPCOA.  

Agitating about leaving the JPCOA has rattled allies, but has served one incredibly important purpose: making banks and businesses hesitant to invest in Iran out of an excess of caution that they might run afoul of current or future sanctions against Iran’s other behavior. Just as Iran is not bound by activity not covered by the JPCOA, so the U.S. is free to take actions not constrained by the agreement. By doing so, the Trump administration is succeeding at denying Iran its main benefit from the agreement: international investment. But if America leaves the JPCOA, foreign governments are likely to provide political cover to their businesses to engage Iran. The U.S. will exchange a strong position for a weaker one.

Some sharp analysts suggest mechanics may allow the president to run a complicated gauntlet of reporting to Congress that Iran is not complying with the spirit of the agreement but leave Congress to decide whether the United States should withdraw from the agreement. The legislation that established certification (which is a wholly domestic creation by the U.S.) would create this opportunity. It would parallel the president’s tactics on other high-profile issues.

The notion is problematic for several reasons. It suggests an elegance of plotting that the administration has given little evidence of possessing. It would place the White House in the position of lobbying Congress to take action contravening what the White House will just have done—so that all the benefits accrue to the president, the costs to Congress. And as the parallel cases make clear, Congress is unlikely to trust the president enough to make a brave choice—which remaining in the agreement after the president decertifies it would be—they suspect he would then publicly castigate them for. Any strategy that requires heroic action by the legislature after the commander in chief shirked his is bound to fail.