Hillary Clinton on Sunday posted a flowery fake letter from President John F. Kennedy to Soviet Premier Nikita Khrushchev to mock President Trump's recent, casually worded missive to Turkish President Recep Tayyip Erdoğan, but the Twitter mockery quickly blew back in Clinton's face, with commentators across the political spectrum suggesting the former secretary of state shouldn't relish so openly in Twitter trolling.

What's more, users quickly noted that Clinton's team had lifted the letter, without attribution, from a segment on "Jimmy Kimmel Live" that aired this past Wednesday night.

The kerfuffle came as Clinton's feud with Tulsi Gabbard has prompted speculation that she might enter the presidential race — and a dare from Gabbard to do just that.

"Dear Premier Kruschev," the mock letter "from the archives" during the Cuban Missile Crisis began, "Don't be a d--k, ok? Get your missiles out of Cuba. ... Give you a jingle later. Hugs."

In his Oct. 9 letter to Erdoğan, first obtained by the Fox Business Network's Trish Regan, Trump adopted a similarly familiar tone.

"Let's work out a good deal!" Trump began. "You don't want to be responsible for slaughtering thousands of people, and I don't want to be responsible for destroying the Turkish economy - and I will. I've already given you a little sample with respect to Pastor Brunson." Brunson was held as a prisoner in Turkey for two years before the Trump administration secured his release.

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Trump continued: "Don't let the world down. ... History will look upon you favorably if you get this done the right and humane way. It will look upon you forever as the devil if good things don't happen. Don't be a tough guy. Don't be a fool. I will call you later."

Sources close to Erdoğan told the BBC Thursday that the Turkish strongman "thoroughly rejected" the letter. Erdoğan reportedly took the letter warning against being a "fool" and tossed it "in the bin," the sources said.

But Clinton's jab itself inspired a slew of mockery — including a post that highlighted Clinton's October 2016 tweet, featuring a photo of herself as a little girl with the caption: "Happy birthday to this future president."

The Washington Examiner's Jerry Dunleavy flagged that the letter had appeared on Jimmy Kimmel's show. The Washington Post's Glenn Kessler remarked dryly, "Sometimes silence is golden."

Trump 2020 campaign senior adviser Lara Trump earlier this month welcomed a possible Clinton presidential run in 2020, saying she was confident the president would defeat Clinton again.

"First of all, I just want to double down on the president and say if Hillary Clinton would like round two with Donald Trump, please let's do that," the wife of the president's son Eric Trump said on "Hannity."

"I would love to see a 'round two' between Donald Trump and Hillary Clinton because I think we all remember, Sean, not too long ago, all the media said that she was going to be the next president. We see Donald Trump in the White House now."

Clinton herself had sparked a wave of speculation about a possible run with a pointed Oct. 8 tweet.

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"I think that Crooked Hillary Clinton should enter the race to try and steal it away from Uber Left Elizabeth Warren," the president wrote. "Only one condition. The Crooked one must explain all of her high crimes and misdemeanors including how & why she deleted 33,000 Emails AFTER getting 'C' Subpoena!"

"Don't tempt me. Do your job," Clinton wrote back.

Fox News' Victor Garcia contributed to this report.