Trump is president of the United States. By virtue of the US Constitution, he is the leader of the executive branch, thus he can order the appointment of a special counsel; he can order an investigation be conducted by DOJ; he can fire Sessions, Rosenstein, or Mueller. He has chosen to do none of these things.
My theory is this is because a well thought out plan is unfolding and this plan will take some time.
We need to exercise patience, not conduct circular firing squads.
As a very astute person recently pointed out:
Because firing a Special Prosecutor worked out so well for Nixon.
Even Trump’s own party has threatened impeachment if Sessions is fired. Trump floated the idea and got enough blowback to heat Antarctica.
Mueller has promised more obstruction investigations if Sessions or Rosenstein are fired. The anti-Trump trio has laid the trap, and it’s an insidious one. Indeed, it’s a coup attempt. I pray Trump survives it.