The Gators in the swamp are eating each other
Trump doesn’t want any permanent appointments. They require approval and scrutiny, which even with his Right sided Senate are sometimes turned back. Anyone who works for Trump is of doubtful moral character from the get go.
Families all over Washington once again lock their doors and tremble at the prospect of a midnight knock on the door and the demand that he become secretary of defense, she become secretary of the interior and their puppy dog Captain Fluffybum has just been promoted to Whitehouse chief of staff
Shanahan knows what's coming and decided to get out before the shit hits the fan.