President Trump and President Volodymyr Zelensky of Ukraine traded barbs today in a demonstration of the remarkable deterioration of the U.S.-Ukraine alliance.

First, Zelensky summoned reporters to his office in Kyiv in part to reject Trump’s false claim that Ukraine had started the war. The Ukrainian leader offered some of his most overt criticism yet of the U.S. president, saying that Trump was living in a “web of disinformation.”

In a social media post littered with falsehoods, Trump responded that Zelensky was a “dictator without elections” who took money from the U.S. to go to war with Russia and “has done a terrible job.” He also suggested that Ukraine’s future security would not be the America’s problem. “We have a big, beautiful Ocean as separation,” Trump said.

The comments were the latest move in what Peter Baker, our chief White House correspondent, described as “one of the most jaw-dropping pivots in American foreign policy in generations.” Trump, as Peter explained, has made clear that he is essentially done viewing Russia as a adversary.

In Ukraine, Trump’s comments have left many people stunned and disillusioned.

In Russia, residents expressed optimism — even glee — that their country’s shunning would soon end.

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