Since President Trump announced his decision to withdraw from the Iran nuclear deal, legal scholars, elected officials, and political commentators have suggested that the non-binding nature of the Iran deal rendered it fatally fragile, and, as Professor Jack Goldsmith wrote, “The particular manner in which President Obama crafted the Iran deal paved the way for President Trump to withdraw from it.” Senator Ben Sasse (R-Neb.) put out a statement representing this view: “Donald Trump isn’t ripping up a treaty; he’s walking away from Barack Obama’s personal pledge.” Eli Lake, a columnist for Bloomberg View who has long opposed the Iran deal, quipped, “If only there was a clause in the constitution that would make these kinds of international agreements more durable.” Had President Obama negotiated the Iran deal as an Article II Treaty requiring a two-thirds vote in the Senate, the argument goes, President Trump couldn’t have—or perhaps wouldn’t have—withdrawn from it. While that view might be consistent with the Founding Fathers’ intent in drafting the Treaty Clause, recent history suggests this view is incorrect. Presidents Jimmy Carter and George W. Bush both unilaterally withdrew from Article II Treaties, without a vote from Congress, and courts dismissed lawsuits challenging their authority to do so. Negotiating the Iran deal as an Article II Treaty would not have stopped President Trump from unilaterally withdrawing from it.

Even had the Senate been willing and able to pass any version of an agreement with Iran in treaty form, a highly dubious notion,* there’s nothing to suggest President Trump wouldn’t have walked away from the deal. While the Constitution’s Treaty Clause specifies clear procedures for entering Treaties—a two-thirds vote from Congress and ratification by the President—it does not set forth any exit process. The Restatement of the Foreign Relations Law of the United States (Third) concluded that the power to terminate or suspend a treaty belongs to the President. In 1978, President Carter announced he was beginning a process to withdraw from the Sino-American Mutual Defense Treaty (between the U.S. and Taiwan). Members of Congress argued that violated the Constitution and sued, with the Senate even passing a resolution by a 59-35 vote stating that “approval of the United States Senate is required to terminate any mutual defense treaty between the United States and another nation.” However, in Goldwater v. Carter (1979), the Supreme Court held that the question was non-justiciable: four Justices dismissed the claim on political question grounds, and another on ripeness grounds. In other words, while the Supreme Court in Goldwater did not answer the question of whether a President can lawfully withdraw from an Article II Treaty unilaterally, the decision indicates that courts are unwilling to stand in the way. In effect, then, although two-thirds of the Senate was required to consent to the treaty, President Carter was able to unilaterally withdraw from those treaty obligations all by himself.

In 2001, building on that precedent, President George W. Bush announced his intent to unilaterally withdrew from the Antiballistic Missile Treaty that the United States had signed with the Soviet Union in 1972. The next year, relying on Goldwater v. Carter, a federal district court dismissed a lawsuit brought by 32 Members of the House of Representatives challenging the constitutionality of the President’s unilateral withdrawal.

Based on this history, there is simply no evidence to suggest that President Trump could not have withdrawn from the Iran deal, even if it were an Article II Treaty. Whether or not a President’s unilateral withdrawal from a Treaty violates the Constitution—a question the Supreme Court declined to answer in Goldwater—it’s highly unlikely that anyone could have prevented Trump from doing so.

It’s possible the Senate could have included a reservation, understanding, or declaration upon consenting to such a treaty, outlining specific withdrawal procedures that would be suitable under domestic law. But absent that type of measure, President Trump would have been free to withdraw from the “Iran Nuclear Treaty” unilaterally, without a vote from Congress. Indeed, his lawyers would have advised him that he could do so, and that he wouldn’t have been the first President to do so.

President Trump’s threat to withdraw from NAFTA is also instructive. NAFTA is not an Article II Treaty, but unlike the Iran deal, it required implementing legislation from Congress after the negotiation was complete. While many legal scholars believe that Congress would need to approve any decision by Trump to withdraw from NAFTA, and certainly any move to repeal statutory provisions implementing NAFTA, that hasn’t stopped Trump from threatening to unilaterally pull out of the agreement anyway.

Criticism of the Iran deal as a purely executive agreement also misrepresents the history of congressional involvement in that agreement. In an interview on Fox News, for instance, Treasury Secretary Steve Mnuchin stated that “the previous administration never took this [Iran deal] to Congress to have it passed.” Similarly, in October of last year, Ambassador to the United Nations Nikki Haley incorrectly suggested on ABC that Congress was “never allowed to debate” the Iran deal. (Notably, the current administration has not indicated whether it will bring any agreement with North Korea to Congress for a vote.)

Not only did Congress debate the Iran deal; it voted on the deal in a way that reflected lawmakers’ risk-averse political incentive structure, all with the Obama Administration’s ultimate support. Stung by the consequences of their decision to authorize the 2003 invasion of Iraq, members of Congress have little incentive to take tough votes on foreign policy—even, for instance, on issues as serious as authorizing the use of force against ISIS, or in response to Syria’s use of chemical weapons. So, in 2015, recognizing its own political incentive structure, Congress came up with an innovative solution: allow members to go on record opposing the Iran deal, while making it rather difficult for lawmakers to stop it from going into effect, lest they be blamed for sinking the deal.

The Iran Nuclear Agreement Review Act of 2015, which passed 98-1 in the Senate and 400-25 in the House, was an ex ante congressional act to give Congress the chance to review any agreement concluded on Iran’s nuclear program. The bill was “authored by Senator Corker” according to the Republican Chairman of the Senate Foreign Relations Committee’s website. President Obama, after threatening to veto earlier legislation, worked with Congress on a more palatable draft and signed the bill into law, and Corker was “pleased to see this bill become law so that any final nuclear agreement with Iran will have to go through Congress where the American people will have a say and lawmakers will have a vote.”

The act allowed for a period of Congressional review and for Congress to block the agreement through a resolution of disapproval. A procedural vote on that resolution failed to garner the 60 Senate votes needed to override a filibuster, and the Iran deal went into effect. Meanwhile, Republicans in Congress and a handful of Democrats were able to go on the record opposing the deal.

The reason President Trump withdrew from the Iran deal has nothing to do with whether Congress had a say in the deal—it did. Nor was the withdrawal about whether the Iran deal was a non-binding political agreement or an Article II Treaty. Based on historical precedent, President Trump could have unilaterally withdrawn from an Article II Treaty, too, and there’s nothing to suggest he wouldn’t have done so.

* As one example, just an hour after the Joint Comprehensive Plan of Action was announced in Vienna, Senator Lindsey Graham (R-SC) was already on Morning Joe denouncing it. When asked if he had read the 159-page agreement, he admitted he hadn’t.

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