In rejecting Flynn, I think Trump was attempting to show how honest and transparent he was, and that he would reject wrongdoing no matter who did it. For some reason Trump seems to trust the career bureaucrats of DC, as we have seen recently in his permitting two Federal medical bureaucracy hacks to dictate his actions as President. I thought he was getting less naive about this - and particularly about trusting anybody held over from Obama - but I guess not.
At least he seems to have awakened on the Flynn issue.
Trump was on Fox and Friends this morning and admitted he had no idea how deep and evil the swamp was when he first got to Washington. In hindsight he appears to regret firing Flynn.
He also mentioned the rat Jeff Sessions, which he still seems to believe was his biggest mistake of all. If Sessions would have acted on the tipoff from the NSA’s Rogers that Trump was being spied on, instead of allowing a special counsel to be setup to investigate Trump, instead, non of this would have happened.
As Trump has said many other times, all Sessions would have had to have done is to announce “I was in the campaign so I know there was no collusion, but I will be investigating what my department has been up to” then all the “crossfire’ investigations would have been exposed way back then.