President Trump escalated his continuing war of words with former White House staffer Omarosa Manigault Newman on Tuesday, calling her a "dog" in a morning tweet.

"When you give a crazed, crying lowlife a break, and give her a job at the White House, I guess it just didn’t work out. Good work by General Kelly for quickly firing that dog!"

The big picture: As one former senior White House official told Axios' Jonathan Swan over the weekend: "She may be the purest of all the Trump characters. ... She may be the most Trumpian. She knows media, she knows about physical presence, like Trump does...that's why I think he's rattled."