Rachel Maddow pointed out last night that with the shocking firing of FBI counterintelligence official Peter Strzok, Trump has forced out almost every single witness to James Comey's account of Trump's attempt to obstruct justice.
"In Comey's telling, the president tried to interfere with the FBI investigation of national security adviser Mike Flynn. The president denies did he any such thing, but Comey has back-up," she said.
"He committed to it writing, and then he told all these people at the time so they could corroborate what he said at the time about what happened. And these are not just job titles. There are specific people who had these jobs at the time in counsel. Comey and the corroborating witnesses for Comey.
"Well, it has taken them a little while to get through this list. The only one left is David Bowdich. He had been the number three. Now he's moved up to be number two, not number three. He is the one who personally directed today that counterintelligence chief Peter Strzok be fired, even though it was decided that he should be kept on.
"Bowdich is the only one left for all the corroborating witnesses. James Comey's testimony that the president leaned on him to shut down an open FBI investigation into the national security adviser. Who will back up James Comey?
"If the president leaning on the FBI director is itself a matter of personal criminal high built for the president when it comes to obstruction of justice, who is it now? Once you get rid of the witnesses, then you can tell any story you want about what happened. If all the corroborating witnesses have been picked off and blown up, who is left to say what happened there at all? Who is left to say otherwise now? " she said.
Trump didn't hesitate to destroy the careers of any public servant who presented that threat, she said.
"When they fired Peter Strzok today, supposedly over his private text messages in which he expressed lots of negative political opinions about President Trump and lots of other politicians, too. they did so even though the inspector general noted that there was never any action at the FBI to influence Donald Trump's electoral prospects or anyone else's prospects either, even though he was better placed to do that than almost anyone else in the country."