Washington is full of people who have issued challenges to Russian President Vladimir Putin. He’s been challenged by the State Department to justify his invasion of Ukraine, and by human rights activists to excuse his country’s demonization of homosexuals and the transgendered. He’s been called out by the Defense Department on the Russian military’s increasingly aggressive stance toward its neighbors, and by civil society activists for the repression of dissent.

Among all the challenges issued to Putin, however, the one from Benjamin Wittes, a senior fellow and research director in public law at the Brookings Institution, stands out.

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Wittes has publicly, repeatedly, challenged Putin to a fight.

“It is real,” he said in an interview Monday. “I am prepared to meet him mano a mano any time, any place he lacks the jurisdiction to have me arrested. Everything else is negotiable. The style, the rules. I’ll work with the Kremlin on that.”

Putin, as anyone who pays much attention to the news probably knows, has crafted a hyper-masculine image in Russia, regularly appearing shirtless in photographs and toting a hunting rifle or riding a horse. He puts on hockey gear and plays against former NHL stars in games where he, mysteriously, scores more goals than anyone else.

And perhaps most frequently, he appears dressed in his judogi, demonstrating his Judo technique against top-rated martial artists.

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However, Wittes, who is also the editor-in-chief of the Lawfare blog, has trained as a martial artist himself, and he thinks Putin is a fraud. “He is a phony martial artist who uses these displays of masculinity as a legitimation device of his rule. If you take a close look at any of those videos, what you’ll see is that he’s not repelling devoted attacks. These are very short clips designed to make him look good. I can’t promise that I will kick his ass, but I can promise I won’t try to make him look good,” Wittes says.

Wittes, who holds a second-degree black belt in Taekwondo, describes himself as “proficient but not especially high-ranking” on the scale of martial arts expertise. “I’m in my mid-40s,” he said. “I sit at a desk for a living.”

“People are clearly taking a fall for him,” said Wittes. “I won’t…If he’s not prepared to fight a middle-aged legal writer of no particular distinction, maybe he should knock off the machismo.”

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Wittes is clearly having a little fun at Putin’s expense. “When people behave in a ridiculous fashion, ridicule is a proper response,” he says. He has no realistic expectation that the President of a world power will step into the ring and duke it out with him. But Wittes says he’s also making a more serious point.

In a Facebook post, he wrote, “[Y]es, there is a serious side to all of this. As the great Putin biographer Fiona Hill explained recently on the Lawfare Podcast, these displays of masculinity are important to Putin's image domestically. In my opinion, they are also deeply connected to his aggression against his neighbors, his repression of dissidents, and his grotesque treatment of the LGBT community in Russia.

“So all I'm saying is this: Man up, dude! Either fight a reasonably well-trained but not especially expert middle aged martial artist in a situation in which he's actually allowed to kick your ass without fear of reprisal, or face condemnation worldwide as a wuss.”

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Wittes has gathered some surprisingly high profile support for his bid to mix it up with Putin. When he has tweeted about it, his remarks have been retweeted by former U.S. Ambassador to Russia Michael McFaul. His Facebook post was shared by a senior state department official. And Russian chess grandmaster and noted Putin critic Garry Kasparov tweeted back to Wittes, “Good luck, but keep in mind that Putin's idea of a fair fight is having you beaten by thugs and jailed for assault!”

Wittes recently tweeted a request to Toomas Hendrik Ilves, the president of Estonia, asking if he would volunteer his country to host the match. So far, there’s been no reply, either from the potential host or from Wittes’ prospective opponent.