If this is true, Make Levin is right. Mueller is not making a legal case but a political one. There is nothing illegal in a President firing an AG, but a majority of Democrats in the House could use this flimsy stuff as a pretext to impeach Trump.
Impeach him for thinking about doing something perfectly legal?
Baloney. Just more gossip from unnamed sources familiar with someone who has no clue. Typical journalism in todays world.
Mueller is not making a legal case but a political one
I have come to believe that Mueller was appointed for one reason: so that the DC Establishment could keep Trump in line. For this reason, I expect his investigation to drag on into the 2020 elections. He may or may not indict Trump on anything, but the Establishment believes the threat is enough to make Trump nominally behave himself (in their eyes).