Trump and Sessions. The Mutual Antagonism Continues
The logical questions to ask are "Why does Trump not fire Sessions?" and "Why does Sessions not resign?" The blunt answer is that for their own survival neither acts on those respective questions. Trump will long to fire Sessions but for all his malevolence and buffoonery, he knows that to do so will look like he is subverting, and openly subverting, investigations into his actions. Better people than Trump did such actions and look where it led them, such as Nixon firing his Attorney General as Watergate was breaking forth.
Sessions will not resign, it will look like he is being pushed. He helped initiate this investigation by not setting any blocks as to where it could go, knowing that to do so would look like he is subverting investigations. Put simply, Trump wants staff who would lie down in the road and get run over for him and Sessions refuses to do that. So Trump publicly undermines him time and again, trying to get him to resign, and Sessions doggedly stays put and they wrestle each other while locked in an embrace. It is not pretty, but it has an inevitability about it, and it will likely end either when Trump feels he can sack Sessions and get away with it, or when Trump is removed from office