John Bolton, who served as national security advisor to President Donald Trump during his first term in office, slammed his former boss for the U.S. voting with Russia and North Korea against a UN resolution condemning Moscow for the war in Ukraine.

Bolton called the move “unthinkable” in a CNN interview, saying that NATO was set up to counter Russia and Russia remains the main threat today.

Yet now the United States is turning on its allies and siding with NATO’s “principal adversary” instead. Trump has called Ukrainian President Volodymyr Zelenskyy a “dictator,” but has refused to use that same word to describe Russian President Vladimir Putin.

Asked it that was simply a negotiating strategy, as Trump’s defenders often claim, Bolton said there’s a simpler explanation.

“I think it’s an indication his mind is full of mush and he says whatever comes into it,” Bolton said. “He believes Vladimir Putin is his friend, and y’know you don’t call your friends ‘dictators.’”

Bolton added that Trump hasn’t liked Zelenskyy since the 2019 phone call in which he asked the Ukrainian president for dirt on Joe Biden, leading to his first impeachment.

“So, it’s no sweat off his back to go ahead and call Zelenskyy a dictator,” he said. “This is somebody who is not fit to be president. He can’t tell America’s friends from its enemies.”

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