The world trusts Trump even less than it trusted Bush.

Donald Trump used to love claiming — falsely — that the world was laughing at America under President Barack Obama. The truth was, Obama improved our standing in world leadership across the board.

But under Trump? America really has become a laughingstock.

The latest Gallup poll finds that, since 2016, world approval of American leadership has fallen 18 points, from 48 percent to 30 percent. By contrast, the world now approves of Chinese leadership by 31 percent.

The losses were biggest among our allies in Canada, Australia, and much of Europe and the Americas.

The last time U.S. leadership numbers were even close to this bad was in 2008, as the presidency of George W. Bush was winding down and we were mired in a protracted war that most of the world saw as illegal. At that time, America had a leadership approval rating of 34 percent, but it rebounded under President Obama and never dipped under 40 percent during his time in office.

Trump has alienated the world with a parade of nonsensical, blind nativism. He enraged the world by exiting the Paris climate agreement, attacking NATO and the U.N., and threatening to blow up the Iran nuclear deal for no reason at all.

He also fails to display the most basic decorum in his capacity as head of state, picking fights with our closest allies and humiliating himself on the global stage. He famously insulted the Australian Prime Minister Malcolm Turnbull, telling him his conversation with Russian President Vladimir Putin was more “pleasant,” and then hanging up on him.

During a trip to France, Trump was caught on camera creepily leering at French first lady Brigitte Macron and praising her “physical shape.”

When German Chancellor Angela Merkel met with him in the Oval Office, he pointedly refused to shake her hand.

The world has good cause to be upset. Trump is not displaying anything that remotely resembles leadership — so our allies have no reason to acknowledge it.