Why as Americans do we allow people like Chavez and other world leaders to come to our country and speak out?

They speak out against our leaders and we should take that as a shot on all Americans. These people get away with coming on OUR land to speak freely. What in the world is going on? If we were to go to another country and speak out against a country and its leader, it would not be tolerated. Wether you like Bush or not, he is our President and how can you not be offended with these tyrants can come over here and do what they do? Its sickening. Chavez has spoke in the past of hating the United States and he is our enemy. The Iran leaders are our enemies. Our enemies do not belong in our country speaking out against us and our leaders. Everyone should ban Citgo gas stations because they are owned by Venezuela.