[estebank]

Death of a President and Vantage Point come to mind. There're many many films that talk about killing the president of the US of A, some using real presidents and in at least one case already mentioned, while that president was in office. You can find it tactless, and I this case painfully unfunny, but that should never stop anyone from doing anything. Specially bit a film. Otherwise there're large swaths of our public libraries that would have to be burned.

[junto]

Ah, yes, but who's the hero? Not the person who assassinates the president right? They are the villains.

I'm playing devil's advocate above, the last sentence was fairly clear about that, just in case you missed it.