People are asking why Sessions doesn't do something.  I believe it is because he recused himself from all investigations related to the so-called collusion with Russia.  Since he recused himself (foolishly in my opinion), he is prevented by law from knowing anything about the so-called Russia matter.  He cannot give advice about it, comment on it, know anything about or receive any communication about it.  He cannot be involved in any way.  Since so many crazy things related to the election are conflated with the Russia thing, Sessions is pretty much prevented from doing anything.  Rosenstein is the person on which the Russia problem landed, but he punted to Mueller.