The US attacked its own people for Oil

Probably the most common claim I have heard in Skypeland, from Arabs, from Americans, from Europeans, and others is that the United States attacked its own people on 9/11 in a false flag operation to justify a war on Iraq to "steal" its oil. When confronted with facts that are contrary to this theory, some start to question it, but some hold frantically to it. It is amazing to me that people just pick up random rumors and elevate them to the status of "proven fact", repeating them over and over, passing them around. When asked how it is possible to both "buy" and "steal" oil at the same time, they often have no response, and are dumbstruck. When confronted with the numbers involved (300 billion dollars a year being spent on 15 billion dollars a year worth of oil), they are a bit confused. When some US military enter the cast and present contrary information, these conspiracy theorists do not know what to say, or claim the military is just brainwashed or giving the company line. People seem to mindlessly repeat things they have seen in youtube broadcasts, or nonsense they have heard from others. They do not try to evaluate other scenarios. They do not try to decide what sounds most likely. They discount contradictory information. They insist on living in fantasy worlds. The only problem is, these beliefs can be dangerous to the peace and security of the world...