(CNN) President Donald Trump is uniquely focused on his place in history. He's forever comparing himself to Abraham Lincoln or tweeting out -- as he did Friday morning -- that his popularity among Republicans is historically high. Trump views himself as a great president and wants to ensure his place in the historical record.

What happened Friday morning in Washington will do that -- although probably not in the way Trump imagined.

In less than 30 minutes, the Democratic-controlled House Judiciary Committee approved two articles of impeachment against Trump, making him only the fourth president in the history of the republic to face a full House vote on impeachment. Two of the three -- Bill Clinton and Andrew Johnson -- were ultimately impeached by the House in a floor vote. The third, Richard Nixon, resigned from office before what would have been a certain full House vote to impeach him.

There's a tendency to lose sight of this historical moment because a) it was totally expected and b) there is very little chance the Senate, where Republicans have the majority, will actually remove Trump from office.

But that would be a mistake. Because impeachment is the most serious thing that Congress can do vis a vis the executive branch. And once triggered, it can't be undone. You can't repeal an impeachment. It's in the history books. Forever.

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