911 was planned by Bin Laden and his group mostly because HE didn't like the US presence in the Middle East as a result of the first gulf war.
I stress HE, because his native country's government along with most in the area, and many from around the world DID want and supported the US presence in the middle east, in order to drive Iraq out of Kuwait.
So basically one guy and his radical group of followers carried out the attack for their own personal reasons.
The US never mistreated Bin Laden or his family that I know of. In fact, he had many family living in the US, plus he was filthy rich..... so there goes the "oppressed" victim argument too.