More from the division its caused than from the actual actions but ------- Lincoln around 1860. 
IMHO, the overwhelming characteristic of the current president is thoughtlessness. Decisions are made from the gut without asking outside advice, without reading anything about the situation, without knowing anything about it. Decisions are made without giving any thought to possible consequences. The capo of the Mafia had to have some foresight to get there.
Not knowing much about it, I wonder if George III would have been comparable.
To me, it’s as if the Know-Nothings had managed to get their 1856 presidential candidate (former president Millard Fillmore) elected and then he cut loose with a nativist anti-Catholic agenda, just updated to a nativist anti-Muslim agenda, “Muslim” in this case expanded to mean “nonwhite”.
Trump is every populist tin-pot half-wit leader brought into power on a wave of nationalism, anti-establishment and anti-corruption, who went on to even greater levels of cronyism, corruption, and national economic disaster.
A quick check of the relevant Lorenz curves makes me think of just-Pre-Revolution France. France. We are a couple of bread riots away from real trouble.
Gone home, your job here is done.
Trump is somewhat analogous to Kaiser Wilhelm II circa turn-of-the-20th-century Europe.
They had in common being nationalists with a highly inflated sense of their own abilities, both prone to embarrassing and self-destructive outbursts, with staff/ministers often scrambling to prevent damaging mistakes on the part of their boss, and engaging in damage control.
To a lesser extent, the eras are similar in that voracious powers and sub-powers are/were jockeying for influence and control, and the actions of one especially volatile leader could provoke major conflicts.
That’s my general feeling as well. But substitute “bread riots” with “inaction-in-the-face-of-climate-change riots”. Let’s hope we won’t get fooled *this *time.