Uh, calling for the death of the POTUS is iffy at best. I mean if he openly wrote about it, who's to say he wouldn't carry out such a thing.
It would have been one thing if he wrote that Obama is a traitor to the United States, and that he should be tried for treason. The secret service takes these things very seriously. So what that means is that we should be extra careful as well when we denounce public figures.
Otherwise, I don't really care about Al Awlaki (or whatever his name was). A better example would have been Obama's mishandling of the whole Benghazi situation.