Why doesn't Trump just fire him?
Trump should fire him for gross negligence in not recusing himself while his wife received the dirty payola. Should anything else be confirmed, well then he has a date with Old Sparky.
Fire him, keep the retirement he is hoping for, he is a crook.
“Why doesn’t Trump just fire him? “
Because he’s learned that “stepping in $hit only makes it stink all the more!” My bet is that he will do nothing to perturb the whole Mueller “investigation,” until it’s over and done with. Then, you will see the bloodletting, and I would not be surprised if he starts with Sessions.