The agreement was designed to keep ground-based nuclear missiles out of Europe, but critics say tearing it up could spark an arms race there.

A piece of reckless brinkmanship that could spark an arms race between NATO and Russia in Europe, or a hardball negotiating strategy that might push Moscow into keeping its longstanding promises on nuclear weapons?

President Donald Trump was widely criticized this weekend when he announced his intention to scrap a landmark nuclear weapons agreement signed by President Ronald Reagan and Soviet leader Mikhail Gorbachev in 1987. The deal was designed to keep ground-based nuclear missiles out of Europe.

Trump said that Russia has for years been violating the Intermediate-range Nuclear Forces Treaty, or INF.

He’s not the first president to make this allegation. President Barack Obama accused Russia of the same.

Many experts agree that Moscow continues to break the rules and flout the pact, but despite that some say ripping up the agreement is a bad idea.

These skeptics range from Sen. Rand Paul, R-Ky., to Gorbachev himself, with the Nobel laureate telling Russia’s Interfax news agency Sunday that Trump’s decision was “very strange” and not the work of “a great mind.”

The White House’s decision to pull out, so this argument goes, will only allow Moscow to continue its current actions without having to maintain the pretense of compliance. Meanwhile, Russia, which also accuses the U.S. of violating the agreement, can point the finger at the U.S. as the one responsible for the INF’s failure.

The 1987 agreement bans ground-based nuclear and conventional missiles that can strike between 300 to 3,400 miles.

“One concern is that in the medium-term there may be the temptation to return intermediate-range missiles, potentially including nuclear weapons, to Europe,” said Karl Dewey, an analyst at Jane’s by IHS Markit, an open-source defense intelligence provider based in London.

All this comes at a time when Trump’s mixed messages have caused alarm among NATO allies about whether the president would truly commit to the principle of mutual defense if Europe were attacked.

“Accompanying any return of nuclear weapons will be the lingering concerns … whether the U.S. would be prepared to protect its European allies in a nuclear war in the European theater — i.e. trade Boston for Berlin, Wisconsin for Warsaw,” Dewey added.

Not only do these critics say Trump’s decision may have dangerous consequences, many were baffled at the rationale and timing of the move.

“Trump’s reasoning is simply: Russia is cheating, so we’re leaving the deal,” Joshua H. Pollack, a senior research associate at the Middlebury Institute of International Studies, wrote on Twitter. “That does fix the problem: Russia will follow suit and then no longer be cheating as they ramp up long-range cruise missile deployments.”

“How does that advance U.S. interests, you ask?” he added. “Your guess, dear reader, is as good as mine.”

One explanation might be that Trump is threatening Russia with an arms race it cannot afford in the hope that the prospect of being outgunned and outspent will force it back to the negotiating table.

Tomáš Valášek, director of Carnegie Europe, said there are two broad possible outcomes of Trump’s decision. One is the dangerous escalation that others have cautioned against. The other is possibility that Russia — sensing an expensive tit-for-tat arms build-up with the U.S. and NATO — will re-enter talks.

“I wouldn’t want to put a relative weight to which scenario is more likely: unrestrained competition, or the threat of unrestrained competition leading to a new round of arms control,” he said.

“You could make the case that it’s better for the United States to say: good, if you’re not going to abide by the treaty let’s drop the pretense,” he added. “Let’s imagine that we both get into an all-out arms race … you, Russia, in this particular case will lose, because you don’t have the budget or the technical means to compete with the United States.”

Another potential explanation for Trump’s move is that it will free up the U.S. to explore deploying intermediate, ground-based nuclear weapons in Asia. China is not constrained by the INF so at the moment it is able to deploy weapons that the U.S. is not.

However, it is unclear where and how these weapons might be based. Dewey said that “Washington will still encounter problems with deploying them [in Asia] if they are politically unpopular.”

One place the U.S. might find particular resistance is if it tried to base nuclear weapons in Japan, the only country to experience their power in war, leading it to adopt a pacifist constitution.