@oralloy,
As convincingly demonstrated by the law professor USA Today cited, Moeller has to, at a minimun, recuse himself from any aspect of any investigation relating to the Comey firing and/or any other claims about "obstruction of justice" emanating from Comey.
If he doesn't then, as also noted by the law professor, he should be fired "for cause." Lawyers and people who comprehend them would know this, but the average guy wouldn't understand it, probably.
If Rosenstein has to fire his ass, because he improperly refuse to recuse himself/resign, then the "obstruction of justice" screams from the left will get even louder, however irrational and unjustified they would be.
It would be even worse (for Trump) if Rosenstein improperly refuses to fire him. Then Trump would have to fire Rosenstein and replace him with a Deputy AG who was willing to follow the law. But then the feigned OUTRAGE of the left would be even more unrelenting. Talk about Nixon and watergate would NEVER cease from that quarter.
Trump is doing the smart thing by letting it be, for now, at least. If Moeller goes crazy trying to frame Trump to "exonerate" and vindicate his pal Comey, then he will HAVE to act, but the political fallout will be terrible.
P.S. There appear to be OTHER reasons to fire Moeller for cause too. He, and those he hires to help him, is required to maintain secrecy. But his carefully hand-picked team has only been on job a few days, and supposedly FIVE of his henchmen have ALREADY made leaks to the press. That's incompetence, if nothing else.