Despite his appealing to supporters in Venezuela with frantic cries of CIA targeting, Chavez is a world leader. He speaks not to one audience, but to two or more. That's why he is losing it. He will not increase his standing or influence internationally by ranting about CIA plots to kill him. He will decrease it.
And no, the United States does not have a stellar history in Latin America. But that does not mean that anyone is trying to kill Chavez now. He is not so important, nor such a threat, that he would be worth it.
What would killing Chavez do? Nothing really. Another person would take his place to complain about the U.S.
Econo-Girl maintains that if the CIA was really intent on killing Chavez, we'd all be talking about his death instead of the prospect of it. Not that the CIA does that kind of thing these days anyway. It's not like it was a successful strategy in the past. Remember the exploding cigars?