Rep. Thomas Massie (R-Ky.) just introduced a bill that would yank the United States out of NATO entirely, turning up the volume on a Republican fight over America's most important military alliance at the exact moment President Donald Trump is squeezing European allies to spend more on defense.

The Bill Would Cut Funding and Trigger Formal Withdrawal

Massie's legislation, H.R. 6508—which he's calling the NATO Act—would force the president to formally notify allies that America is out under Article 13 of the North Atlantic Treaty. It would also shut off all U.S. taxpayer money flowing to NATO's shared budgets, including civil, military and infrastructure funds.

"NATO is a Cold War relic. We should withdraw from NATO and use that money to defend our own country, not socialist countries," Massie said in a press release on Tuesday, adding, "America should not be the world's security blanket—especially when wealthy countries refuse to pay for their own defense."

Rep. Anna Paulina Luna (R-Fla.) is co-sponsoring the measure, and Sen. Mike Lee (R-Utah) filed companion legislation in the Senate.

Legal Roadblocks and Public Support Stand in the Way

Here's the problem: Congress passed a law in 2023 specifically designed to prevent any president from walking away from NATO on their own. That law requires approval from two-thirds of the Senate or an act of Congress before the U.S. can formally exit the alliance. So Massie's bill would need significant bipartisan backing to actually go anywhere.

Public opinion isn't exactly on his side either. An AP-NORC poll in 2024 found 61% of Americans believe NATO membership is good for the United States. Pew Research reported in 2025 that six in 10 adults view the alliance favorably, with support strongest among Democrats but still substantial among Republicans.

Trump Keeps Squeezing Allies on Defense Budgets

Meanwhile, Trump has spent months making NATO members sweat over their defense budgets. According to two separate reports from Reuters in 2024, he told one interviewer the United States would only help protect NATO members "if" they paid more, and even suggested he would encourage Russia to act against countries that don't pull their weight—a comment that sparked immediate backlash.

The pressure worked, at least partly. NATO leaders this year adopted a new pledge to spend 5% of GDP on defense by 2035, including a 3.5% floor for core military outlays. That's a significant jump from the previous 2% target many countries were already struggling to meet.