President Trump has no need to fire Rosenstein (as long as he knows Rosenstien is not wiretapping him) because the deputy attorney general, in addition to having wanted to secretly record his in-person conversations with Trump, signed-off on the fourth FISA warrant, against Carter Page, which like the other three FISA warrants predicated on the ridiculous Golden Shower Dossier provided by Hillary, so Rosenstein will be resigning to defend himself in court.