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Trump keeps attacking his most Trumpian cabinet official.

This morning the president asked:

This tweet is remarkable in several ways. First, Trump is openly politicizing the Department of Justice by calling for the prosecution of a political opponent, with the implied threat that he’ll fire Attorney General Jeff Sessions if that threat isn’t carried out.

The tweet is further evidence of Trump’s unhappiness with Sessions, following up on comments the president made in a New York Times interview last week. This rift is all the more remarkable because the two men are, on paper, ideological allies. Sessions was the first senator to endorse Trump, and has been the most effective cabinet member in making Trumpism a reality, leading an immigration crackdown and issuing extreme law-and-order measures. Sessions is—or at least was—extremely popular among Trump’s ethnonationalist supporters.

Trump is clearly contemplating firing Sessions, which would clear the way for hiring a new attorney general who hasn’t been recused from the Russia investigation and who would be free to fire special counsel Robert Mueller. The fact that Trump is turning on so important a political ally as Sessions is further proof of how much the Russia investigation scares the president.