Protesters don Putin and Trump masks during a demonstration against U.S. withdrawal from the INF treaty on February 1, 2019. Photo: picture alliance/picture alliance via Getty Image

President Trump just delivered what was probably the death blow to one of the underpinnings of 30 years of peace in Europe, announcing the suspension of the Intermediate-Range Nuclear Forces Treaty. The move could irreparably damage prospects for further international arms limits, just as we’re experiencing rapid technological change and heightened great power rivalry. Thus, it’s time for Americans to reconsider what kind of posture we should set with the world’s deadliest weapons — and the 2020 presidential contest may be the venue for that debate.

The landmark 1987 agreement bars the U.S. and Russia from fielding ground-launched cruise missiles that can fly between 310 and 3,420 miles, the range Washington or Moscow would use to hit targets in Europe. In a statement released Monday morning, President Trump said the U.S. will suspend its compliance with the INF Treaty on Saturday and begin the withdrawal process, “which will be completed in six months unless Russia comes back into compliance by destroying all of its violating missiles, launchers, and associated equipment.”

“We cannot be the only country in the world unilaterally bound by this treaty, or any other,” Trump added. “We will move forward with developing our own military response options and will work with NATO and our other allies and partners to deny Russia any military advantage from its unlawful conduct.”

The Trump administration has telegraphed this move for several months. It’s a response to Russia’s new SSC-8 ground-fired cruise missile — which violates the treaty, according to both the U.S. and NATO — and more broadly, to concerns that China is building a large stock of intermediate-range nuclear missiles. The accord has constrained Washington’s efforts to counter China’s militarization of the South China Sea.

The Obama administration accused Russia of violating the INF Treaty in 2014, but Moscow was adamant that it would not cancel the missile system, and eventually claimed that Washington had flouted its terms as well. With each side alleging violations, the treaty seemed in bad shape even before the Trump administration developed an interest in building and deploying intermediate-range nuclear missiles of its own.

The problem at hand is much broader than any specific missile system; it’s the demise of the principles underlying the treaty that we should really worry about. The treaty signaled a profound interrelationship between U.S. and European defenses, such that Moscow would always have to worry that an attack on Europe would be met by a stronger counterattack from the U.S. That, our European allies believed, still constrained Moscow from building even more weapons targeting Europe — and perhaps just as important, from applying pressure through cyberwarfare, influence operations, and other nonmilitary measures. Obviously, you don’t need a treaty suspension to tell you the security ties between Washington and Europe are unraveling. But for a relationship that was always based on the assumption of deterrence, this is a significant blow.

The INF Treaty — negotiated between Presidents Reagan and Gorbachev — was also a model for internationalizing the risk of nuclear war through intrusive inspections and extensive information sharing. It paved the way for conventional arms treaties that came after it as the Cold War was ending, and for the kinds of deals Washington got from Iran and has demanded from North Korea. If the United States is no longer willing to share that kind of information about its own forces, or to use its human and technological resources to get that information from others, then other efforts to curb nuclear and conventional weapons are in deep, deep trouble.

The weapons prohibited by the INF Treaty were seen as uniquely destabilizing, as their shorter flight times demanded even faster decisions, potentially unleashing full-on nuclear war in less time than it takes the president to compose a tweet. In the 1980s, Washington and Moscow led in cementing a global consensus that such weapons should not be built or deployed. Today, China is building them by the dozens, Moscow has brought its system on line, and some Pentagon officials and GOP national security circles want similar weapons.

Arms-control advocates have long countered that the U.S. should negotiate a trilateral agreement with Russia and China to limit intermediate-range weapons. But the Trump administration was uninterested — and it’s fair to say that Beijing sees little to gain from such an agreement either.

Instead, the Trump administration began development of its own intermediate-range weapons a year ago, and has spoken to defense firms about plans for others. In case anyone missed the message that the administration likes nuclear weapons and wants to field more of them, news broke this week that the U.S. Department of Energy has started making new “small” nuclear weapons (i.e. weapons with one-half to one-third the power of the bombs used on Hiroshima and Nagasaki).

These developments were approved by Congress back in 2017, but following the 2018 midterm elections, some lawmakers have been pressing to take another look. They are led by Democratic congressman Adam Smith of Washington, the new chair of the powerful House Armed Services Committee. Smith has said he will try to ban the smallest weapons and redo the administration’s entire approach to nuclear weapons, spelled out in the most recent Nuclear Policy Review. That may seem like a tall order when Democrats control just one house of Congress, but Smith can — if he chooses to — make sure that these issues get the kind of loud public debate they haven’t had in a generation. And he can team up with fiscal hawks in both parties to insist that the Pentagon make choices — for instance, between adding nuclear submarines and surface ships, or launching new missile systems and ambitious aviation expansions (like Trump’s proposed Space Force).

It looks like Smith will have some help from the 2020 presidential class. This week, the congressman teamed up with Senator Elizabeth Warren to introduce a bill that would commit the United States to launching nuclear weapons only in response to their use by another nation. The so-called “No First Use” policy is hotly debated by nuclear experts, and is unlikely to reach the floor for a vote, much less pass — but the bill does draw attention to the administration’s interest in developing weapons explicitly designed for first use. Meanwhile, Senator Jeff Merkley introduced legislation that would bar the Pentagon from developing weapons that were banned under the INF Treaty unless a U.S. ally specifically offers to host them. Many of the bill’s sponsors are either already running for president or rumored to be considering it; the list includes Senators Warren, Kirsten Gillibrand, Bernie Sanders, Kamala Harris, and Sherrod Brown.

Don’t dismiss this as just 2020 positioning. Washington’s nuclear posture, essentially unchanged since the Cold War, is fraying from all sides. Conservatives say that China’s major weapons upgrades, the emergence of North Korea as a nuclear power, and a more hostile Russia all mean that Washington should up its nuclear game — and possibly even take another look at using nuclear weapons on the battlefield.

That idea was broadly discredited during the Cold War. (There is no such thing as a nuclear weapon, even a “small” one, that only ruins half of your day.) But on questions from whether cyberwar and hypersonic weapons change the foundations of nuclear theory, to how to live with a nuclear North Korea, to how to respond to China’s growing arsenal, opponents of the administration’s policies are going to have to come up with serious, fleshed-out alternatives. That kind of debate only comes around once in a generation, and it looks as if it has arrived.