Interestingly, Sessions may have done Trump a favor by resigning instead of demanding to be fired. Actually getting fired might have limited the authority of his acting successor:
https://www.bloomberg.com/news/arti...-or-get-fired-mueller-fate-may-hang-on-answerUnder the Federal Vacancies Reform Act, Trump can appoint an acting official without Senate confirmation if he replaces someone who has been incapacitated or resigned. It doesn’t apply if the previous official was fired. Sessions began his resignation letter by saying he was leaving at Trump’s request.
