What did Donald Trump do today?

He accidentally told the truth about William Barr.

In an interview tonight, Trump told Fox News that if Attorney General William Barr had been in office from the start, "this all would not have happened." In other words, Trump is saying he believes that Barr would not have appointed a special counsel to investigate his and his campaign's ties to the Russian government's attempts to throw the election to him.

This is almost certainly true. 

Trump spent much of his first two years as president attempting to hound his first attorney general, Jefferson Sessions, from office. Sessions, who was part of the Trump campaign and himself had secret meetings with Russian agents that he lied about to Congress, had recused himself from the FBI's investigation into that attack. Replacing Sessions would have allowed Trump to put a loyalist in charge of the Mueller investigation directly.

Barr wrote an unsolicited memo to the Department of Justice arguing that Trump could never be guilty of obstruction of justice while in office. This memo was brought to the attention of Trump, who then appointed him to replace Sessions, who he had fired after the midterm elections in November. 

Barr then used that authority to pre-emptively declare Trump innocent of obstruction, which Mueller had pointedly refused to do. 

In his summary of the still unseen Mueller report, which apparently runs into the hundreds if not thousands of pages, Barr argued that Trump should not be prosecuted for obstruction if he could not be prosecuted for an underlying crime. This is legally backward—obstruction of justice is a crime in and of itself, because if it were not, there would be no reason for criminals not to try to obstruct investigations into their crimes.

In short, Barr as attorney general absolved Trump after less than two days of the crime he had promised to absolve Trump of when he was a private citizen waiting to be nominated.

Why does this matter?

• The attorney general is not the president's personal defense attorney.

• It's bad if the president needs the attorney general to act as his own defense attorney.

• The president is not above the law.