Mission accomplished? After a contentious NATO summit, Donald Trump held a surprise press conference earlier today to announce substantial increases in spending commitments by other members of the alliance. Trump declared NATO now a “fine-tuned machine” after his negotiations, but also hinted that he could have disassembled it if he wanted:

President Donald Trump declared NATO a “fine-tuned machine” in an impromptu news conference at the conclusion of his participation in a contentious NATO summit during which he has questioned the utility of the alliance and harshly criticized some of the United States’ closest allies for not paying more into the alliance.

The alliance is much stronger than it was at the outset of the conference, Trump said Thursday, taking credit for what he said are increased commitments from allies to up spending, citing an increased commitment of $33 billion to the alliance.

“Yesterday, I let them know that I was extremely unhappy with what was happening and they have substantially upped their commitment and now we’re very happy, and have a very, very powerful, very strong NATO; much stronger than it was two days ago,” Trump said.

The president told reporters he “probably” had the unilateral power to pull the United States out of NATO if he chose to do so but said he thinks it’s unnecessary.

Not only is that a foolish thing to say, it’s at least technically untrue. The NATO treaty was ratified by the Senate in August 1949, giving it the force of law, which means — theoretically, anyway — that Congress would have to act to formally undo it. In practice, though, Jimmy Carter unilaterally canceled a ratified defense treaty with Taiwan in 1978 without any action from Congress, and without any penalties except some political damage that largely got forgotten in the Iranian crisis the next year. Congress might take stronger action against a president that abruptly denounced our NATO membership, especially with this president.

Even apart from that, it’s still foolish, considering how much the US relies on its NATO partners for security and military operations that go far beyond Europe. It’s the equivalent of cutting off one’s nose to spite one’s face. And yet Reuters claims that Trump leveled that threat as a means to getting the contribution increases he demanded:

U.S. President Donald Trump told NATO allies in a closed-door meeting on Thursday that governments needed to raise spending to 2 percent of economic output by January next year or the United States would go its own way, two people familiar with the discussions told Reuters.

The ultimatum was delivered in a session at the NATO summit, the sources said. “He said they must raise spending by January 2019 or the United States would go it alone,” one person said.

French president Emmanuel Macron denied that any threat ever was aired, publicly or privately:

Maybe not, but the private meeting featured some “intense” back and forth anyway, according to one of Trump’s targets:

Merkel said: “We had a very intense summit.” …

The mood had appeared to have calmed as the summit went into its second day, focusing on operations beyond Europe. But, several sources said, Trump instead reopened in strong terms his demand that other countries spend more immediately.

“The language was much tougher today,” one source told Reuters. “His harshest words were directed at Germany, including by calling her Angela —‘You, Angela.’”

As well as Merkel, Spanish Prime Minister Pedro Sanchez and Charles Michel, the prime minister of Belgium, were singled out by Trump for undershooting on their spending targets when U.S. taxpayers, funding a defense budget worth about 3.6 percent of their national income, foot much of NATO’s bills.

In the end, Trump got the other NATO members to agree to his terms. That’s why he held a press conference to declare victory, but it’s likely only a momentary win. NATO members have been pledging increases for years, only to fall short later. Their countries aren’t fond of the idea of spending more money on defense, a legitimate frustration for the US.

Perhaps Trump thought that threats of breaking the alliance might finally wake them up, but those are very likely to have more effect on NATO’s opponents and enemies, who have waited almost 70 years for the alliance to fall apart. Airing notions of unilateral withdrawal in public over $33 billion in pledges is pennywise and pound-foolish in a world where Russia is actively rebuilding its empire by force in places like Georgia and Ukraine. And when those pledges fall short, you can bet your bottom dollar that Vladimir Putin will have Russia’s propaganda machine making the most of it, hoping to break the last threads of the alliance that broke the Soviet Union and kept Russia out of eastern Europe since then.