I know nothing about civil-engineering and, to be sincere, I doubt that the destruction of two sky-scrapers would be needed for a sufficient provocation. It looks like an overkill, doesn't it?
That being said, the official War on Terror narrative is definitely fragile and we are presented with a distorted image.

Firstly, I think that the reason behind it are geo-politic interests, like the Iraqi oil being sold and exploited by American companies and not the Iraqi state, not a crusage againt violence and bigotry, and secondly, movies have led us to view wars as a simplified stugggle between us and them.

Well, it usually is more complicated, with temporary alliances, cynical deals under the table, doube agents and conflicting interests.