If the tyrant goes against established law, yes.

(an aside but the majority of the US population didn't elect Trump. He is in office because of the electoral college. Might seem like a distinction without a difference but I think it matters when we're implying personal culpability)

No.

First term he lost the popular vote, second term he won it.

If you just mean a majority of eligible voters did not vote for Trump, that’s true for every US President in my lifetime.