Biden tells the world "America is back." The world isn’t so sure.

But it’s increasingly clear that Biden cannot simply sweep up the broken diplomatic china and restore the world order that reigned when he was vice president. There is one simple reason: Allies know Trumpism could always come back, either in a 2024 bid by Trump himself or from another presidential hopeful offering a similar pitch.

That has left friends and foes alike with doubts about the value of any new American commitments, given the country’s deep political divide and the possibility that the pendulum could swing back in four years. Allies have begun hedging their bets, musing about a Europe-only security force and exploring wider trade with China.

That’s even true for America’s closest allies, like Great Britain. “The Bidenites say with good reason that they recognize that ‘not politics as usual’ was the theme of the election in the past few years,” Karen Pierce, Britain’s ambassador to the United States, said. “It is a theme that they know they’re going to have to contend with.”