The Senate Tried to Trump-Proof NATO. Now They Hope Their Effort Worked.

A 2023 law, co-sponsored by Trump’s secretary of state pick, Marco Rubio, is giving senators some assurance, as it makes it much harder for the U.S. to withdraw from NATO.

The flags of the USA and NATO.

Withdrawal from NATO now requires a two-thirds majority vote in the Senate. Thomas Trutschel/picture-alliance/dpa/AP Images

President-elect Donald Trump has long mused about withdrawing the U.S. from NATO, and his election is making international leaders anxious that he’ll make good on his promise. But senators say that, other than bringing Trump to court if he tried to withdraw, they’ve done all they can do to protect the treaty.

Thanks to a 2023 measure authored by Democratic Sen. Tim Kaine and Republican Sen. Marco Rubio, withdrawal from NATO now requires a two-thirds majority vote in the Senate or an authorizing act from Congress.

“We’ve protected NATO,” Kaine told reporters Tuesday. “If he tries to withdraw, we’ll beat him in court.”