The three people with the greatest power over Donald Trump’s political future are Senate Majority Leader Mitch McConnell, Special Counsel Robert Mueller, and Trump himself.

And if the president’s recent treatment of McConnell and Mueller is any indication, Trump had better watch out.

The president is on a sustained campaign against the leader of the Senate. For the second day in a row, Trump broke from his vacation to attack the Kentuckian:

The tweet came 10 minutes after Trump was scheduled to lunch with Vice President Pence, who has been an intermediary between Capitol Hill and the White House.

Later Thursday afternoon, during a brief press appearance, he once again attacked McConnell for the failure of a Senate attempt to repeal Obamacare. “I said, ‘Mitch, get to work and let’s get it done,’” he said. “They should have had this last one done. They lost by one vote. For a thing like that to happen is a disgrace. And frankly it shouldn’t have happened, that I can tell you.”