It will now be even harder for Trump to fire Mueller. Capitol Hill already would have gone crazy if Trump tried that. But after Mueller has done such substantive work — even earning the lavish praise of Trump lawyer John Dowd — it’s impossible to imagine Trump getting away with firing him.

The fact that Deputy Attorney General Rod Rosenstein gave a press conference is significant. It was a major vote of confidence in the Mueller probe: This is Rosenstein saying he’s proud of this work, and fully supports it.

It’s also a notable show of independence by Rosenstein — a Heisman to the White House.