Why is it surprising? America can't go against every one who doesn't agree with them. It needs to weigh its options carefully and intelligently. The mere reason that Hugo Chavez is still in power testifies to this fact.

The world is not black and white where we might send CIA or Special Forces to neutralize someone who we don't like. It's definitely more complicated than it seems.

There are other, more indirect ways to neutralize what he's doing. A good one is using the media to sway public opinion, etc. Another one is to discredit the guy by linking him to some "terrorist group/government" and say they're funding him, etc.