Since an unsustainable situation won’t go on forever, it seems that something will have to put an end to the Trump (mal)Administration. But what?
He could be removed from office by impeachment and conviction, and that’s obviously the right course of action. But – for the moment – it’s equally obviously infeasible politically.
He could also – once Mueller has done his job – be indicted for and convicted of a variety of crimes, but there’s some doubt as to whether a sitting President can be indicted. (I think he can, since the Constitution does not protect him as it protects Members of Congress, but there’s no precedent and therefore no authoritative statement of the law.)
On the other hand, he could clearly be indicted for state crimes by state prosecutors, and the New York AG might have the nerve to do it and the skill to obtain a conviction. That little-discussed option might be the actual outcome, but it’s not on the horizon right now.