'Useful American idiot' Trump facing furious backlash for boasting about Putin closeness
Kremlin photos of Putin and Trump

Donald Trump saying he was the "apple" of Vladimir Putin's eye is sparking some harsh criticism.

Trump, who has long been open about having a good relationship with the Russian president, reportedly said in a Fox interview that Putin never would have invaded Ukraine if he had been president. "I was the apple of his eye," the former president said in the interview.

The response was swift.

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David Frum, a former speechwriter for President George W. Bush, said helping Trump to become the president was Putin's "supreme accomplishment as dictator."

"A perverse truth here. Helping Trump into the US presidency was Putin's supreme accomplishment as dictator. A Trump 2nd term would have wrecked NATO from within," Frum wrote Saturday. "With no one to help it, Ukraine would have been easy pickings for Putin."

Conservative attorney and Trump-critic George Conway also chimed in, calling Trump a "Kremlin asset."

“'I was the apple of his eye.' — Kremlin asset D. J. Trump, on his 'relationship' with V. V. Putin."

MSNBC host Mehdi Hasan attempted to put the development in a totally different perspective for those who might not be taking the incident seriously.

"Imagine, just imagine, if Barack Obama in any of his 8 years in office had proudly and publicly referred to himself as ‘the apple of [Putin’s] eye,'" he wrote Friday. "The right would have had an immediate and nonstop meltdown. Fox would have demanded impeachment and indictment 24/7."

Presidential historian Michael Beschloss took a more historical approach:

"Never heard Truman boast of being the 'apple' of Stalin’s eye," he said.

Ron Filipkowski, a former Republican, had an extremely simple response.

"Yeah, we know. Putin’s most useful American idiot," he wrote.