In a rare show of emotion at the Pentagon, press secretary John Kirby choked up discussing Russian President Vladimir Putin and alleged Russian atrocities in Ukraine during a briefing with reporters Friday.

       It began when Kirby was asked whether he believes Putin is a "rational actor."

       "It's hard to look at what he's doing in Ukraine, what his forces are doing in Ukraine, and think that any ethical, moral individual could justify that. It's difficult to look at the –" Kirby said, cutting off his sentence as he looked away to collect himself.

       Manuel Balce Ceneta/AP

       Pentagon spokesman John Kirby speaks during a briefing at the Pentagon in Washington, D.C., April 29, 2022.

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       After eight seconds of silence behind the podium, he continued.

       "Sorry," he said. "It's difficult to look at some of the images and imagine that any well-thinking, serious, mature leader would do that. So, I can't talk to his psychology, but I think we can all speak to his depravity."

       Later in the briefing, he apologized for the charged moment.

       Rodrigo Abd/AP

       Police officers work on identifying bodies of civilians, before sending them to the morgue, in Bucha, northwest of Kyiv, Ukraine, on April 6, 2022.

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       "I didn't mean to get emotional, I apologize for that. I don't want to make this about me. But I've been around the military a long, long time and I've known friends who didn't make it back. It's just hard," Kirby said.

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       Kirby then redoubled his attack on Putin and the brutality he said has been carried out by his military -- accusations the Russians deny -- his demeanor visibly shifting from sorrowful to indignant.

       "It's hard to square his, let's just call it what it is, his BS – that this is about Nazism in Ukraine, and it's about protecting Russians in Ukraine, and it's about defending Russian national interests, when none of them, none of them were threatened by Ukraine," he said, slamming his right hand to the podium to emphasize the final words.

       Alexey Danichev/SPUTNIK/AFP via Getty Images

       Russian President Vladimir Putin gives a speech at a meeting of advisory council of the Russian parliament in Saint Petersburg, Russia, April 27, 2022.

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       "It's hard to square that rhetoric by what he's actually doing inside Ukraine to innocent people. Shot in the back of the head, hands tied behind their backs. Women, pregnant women being killed. Hospitals being bombed. I mean, it's just unconscionable. And I don't know ... I don't have the mental capacity to understand how you connect those two things. It's just beyond me," he said.

       He closed with a final apology.

       "I'm just a spokesman," he said. "I'm not qualified to make an assessment one way or the other, and I do apologize for injecting my personal perspective here."