Probably some of the leftist dictators of South America would qualify. Chavez, Morales et. al.

Yes, but not in the US, as OP was saying.

I assume he was trying to allude to Obama, which at least in the recent decades came the closest to that in terms of media image, but the claim that there has been an anti-imperialist president of the US (on any relevant timescale) doesn't hold up to any scrutiny.

That's what the "would be" indicates directly in front of the part you quoted. And in reference to your comment below, I am definitely not referencing Obama, that doesn't even make sense because he did not dismantle American Empire in his two terms, in addition to not really being a leftist at all.

English is ambiguous. Your statement can be interpreted as "I thought the guy we elected (a specific individual to whom I refer coyly, not by name) would destroy everything" or "I thought it would take electing a certain type of person to destroy everything".