I think historians are smarter than that. Harmless fool or criminal mastermind is an entirely false dichotomy. Trump has made it very plain he is incompetent to an astounding degree and dangerous anyway. I stand by what I said here:
Trump could be impeached now, just for his dramatic violation of the emoluments clause, let alone whatever collusion his clumsy firing of Comey was supposed to conceal. The reason he hasn’t been is not that his ineptness has fooled us all, that in laughing at things like covfefe we are somehow rendered unaware of the damage he is causing, but that the people who should be doing it are motivated to look the other way. Worry about that, not that we are somehow unable to pay attention to two things at once.