When Sean Hannity famously asked, indeed virtually pleaded with, Donald Trump to reassure the public that, if reelected president, he was not serious about using the office in a dictatorial fashion, Trump responded by saying he would not be a dictator “except for Day 1.”
There is no way to know whether Trump is serious—or whether he has the discipline to follow through if he is. Trump’s supporters claimed he was just trolling his critics. Those same critics, however, noted that Trump has been making similar statements for months now and that it’s foolish not to take him seriously. Looking at worst-case scenarios, what could Trump do?
Imagine, for a moment, a newly elected President Trump ending America’s membership in the North Atlantic Treaty Organization (NATO). He repeatedly disparaged the alliance while he was president, and as the New York Times previously reported, “Several times over the course of 2018, Mr. Trump privately said he wanted to withdraw from the North Atlantic Treaty Organization. … Mr. Trump told his top national security officials that he did not see the point of the military alliance, which he presented as a drain on the United States.” So it’s not inconceivable that, on Day 1 in the Oval Office, President Trump—surrounded by national security advisers far more acquiescent to his views than those in 2018—formally announces the United States will be leaving an alliance we have led for nearly three-quarters of a century.
It would be a dangerous strategic step to take. The Biden administration has used NATO as the core of the effort to help support Ukraine since the 2022 Russian invasion: It has added more forces to the European theater and has seen NATO expand to include Finland and, at some point in the future, Sweden. To say Washington’s credibility as an ally and partner on the world stage would be undermined is to state the obvious. But it’s also the kind of move that Trump might see as playing to the isolationist instincts of much of the conservative base here at home.
While the Constitution is clear about the process by which the country enters into a treaty—a president “shall have Power, by and with the Advice and Consent of the Senate, to make Treaties, provided two thirds of the Senators present concur”—the text of the Constitution has nothing specific to say about the requirements for ending the country’s commitment to a treaty.
Arguments have been made that Congress must approve such a decision or that the Senate, given its role in sanctioning a treaty, should also have a say in terminating that pact. Yet presidents acted on their own in the two most recent decisions to end America’s adherence to a security-related treaty. In late 1979, President Jimmy Carter announced that the 1954 security accord with the Republic of China (Taiwan) would end on January 1, 1980. And then, in December 2001, not long after 9/11, George W. Bush announced that the U.S. was pulling out of the Anti-Ballistic Missile Treaty.
Carter’s decision did not go unchallenged. Republican Sen. Barry Goldwater filed a lawsuit in federal court arguing that treaty termination required Senate concurrence. Eventually, the case made it to the Supreme Court, where six of the nine justices ruled that it should be dismissed, with no hearing or oral arguments required. Justice William Rehnquist, concurring with that judgment, issued a statement along with three other justices that said the issue at hand was a political question—a dispute between Congress and the president over how foreign affairs should be conducted—and, therefore, not something for the court to decide. It was up to Congress to defend its claimed prerogatives. Justice Lewis Powell also concurred in the decision, but argued in a separate statement that the case might in fact have been one for the court to hear if the Congress had acted as a whole by passing a resolution formally opposing Carter’s decision.
Goldwater v. Carter (1979) undoubtedly influenced how Congress reacted to Bush’s decision to pull out of the ABM Treaty two decades later. While there were certainly Democrats who criticized the decision, the party itself was in the minority in the House and held a slim, one-vote margin in the Senate. With the precedent of Goldwater v. Carter, individual members stood no chance of contesting the White House in court and, just as importantly, they lacked the political wherewithal to challenge the decision by passing a resolution that the court might have then taken cognizance of.
To meet the potential challenge of a President Trump decision to bail on NATO and also meet the Powell criteria for possibly being able to take such a decision to court, Democratic Sen. Tim Kaine and Republican Sen. Marco Rubio sponsored a measure that was added to the recently passed National Defense Authorization Act that prohibits a president from withdrawing from the alliance without the approval of two-thirds of the Senate or by an act of Congress. To give the measure some teeth, the bill also prohibits the use of appropriated funds for suspending or withdrawing from the treaty in the absence of prior Senate or congressional approval. For those concerned about the mixed signals Congress has been sending about the American commitment to allies and friends in recent weeks and months, the Kaine-Rubio provision is to be commended.
However, the issue is whether the legislation would in fact stop Trump from deciding he had had enough of NATO. The first thing his White House lawyers might say is that Congress’ action was unconstitutional, perhaps quoting Thomas Jefferson in a note to French envoy Citizen Genet in 1790: “The transaction of business with foreign nations is executive altogether. It belongs, then, to the head of that department, except as to such portions of it as are specially submitted to the Senate. Exceptions are to be construed strictly.” As for the prohibition on using monies to carry out a withdrawal, here a White House fact sheet could point to the president’s authority as commander in chief to deploy the armed forces as he sees fit and, in his judgment, as required for the security of the nation. Indeed, falling short of actually pulling troops out of the European theater, President Trump could simply state that because in his judgment allied states were not meeting their commitments to fully reform and rearm their militaries, he was suspending America’s commitment to Article V of the North Atlantic Treaty—the core article that commits each member to consider an attack against another as an attack against them all. There would undoubtedly be an enormous uproar at such a statement but preventing Trump from carrying out that pledge requires more than loud criticism here and abroad.
A president’s institutional capacity to act first and act unilaterally is considerable. And the real check in such a dispute has to be a Senate or Congress in which the majority is willing to put aside party allegiances in favor of institutional loyalties to the chambers themselves. If Trump is elected this November, it seems likely that the GOP will retake the Senate and possibly the House. What is the evidence that a Republican majority might buck the president on NATO? Having the Kaine-Rubio measure on the books is one thing, but forcing a president to bend to its strictures is another.
Perhaps individual members, with the law on the books in hand, would try to involve the court once again. But it remains doubtful, given the silence in the Constitution about how treaties are to be terminated, that the Supreme Court would want to act as the final arbiter over what most of the justices would likely still see as a “political question.”
All of which leads to a more fundamental point: A president’s character is just as important as his policy positions. The office is the man in the end, and how he reads his obligations to faithfully execute the laws of the nation and his office is singularly dependent on that character. Trump may not on Day 1—or on any day—withdraw from NATO. But we do know that, in comparison with the chaos of 2016, his team is far ahead in its planning on what to do if he wins. There will be no Jim Mattis, John Kelly, or John Bolton to hold him back. In short, the best way to keep the United States in NATO is to keep Trump out of the White House.