Question: Does anybody know the cause for America´s involvement?

I´m a vietnamese refuge, who lives in Germany since 1980. German history teachers tell you, that war was waged by the Americans, because one of their warship was bombed in vietnamese territory. Is that true? I know that the U.S.A. always wage war, if they can make profit. You will see, civil wars dominate on land, which is rich in minerals. Then the U.S. Army will invade as "The Savior", so they are legitimated to rebuild the destroyed economy. But all what they do is to americanize and exploit the foreign land. A well-known secret agent named von Bülow, who worked many years for former west-germany as a spy in east-germany, found out that the C.I.A. plans the civil wars. they make two different parties fight against each other. Then something must happen, that the American government can justify its warfare and gain the people´s sympathy. They get oil from Saudi-Arabia, they want to snatch it from Hussein and now they want to put pipelines in Afghanistan. but what was the case in Vietnam? One thing is for sure. they tested their new chemical weaponry as they did in Irak. Here in Germany we know a lot of the intrigues and manipulation of C.I.A. (some may call it Criminals In Action). C.I.A. doesn´t underlie any fundamental law. We also know that the Americans are manipulated by their media. CNN for instance is forced by the U.S. government to filter information.