Nobody has said that they're going to kill Bush.
I can show that this statement is false.
They're saying:
Now the word "Gonna" is (according to dictionary.com) informal usage and is a contract of "going to." The word "President" (again according to dictionary.com) can mean "The chief executive of the United States, serving as both chief of state and chief political executive. " I know some people don't keep up with these things, but the current President's name is Bush.
So...as far as I can tell what is being said is that they're going to kill Bush.
Now I do agree that Bush is the problem, but we should not defend these people by telling everyone that they're not saying what they're really saying.