If Bin Laden only targetted the Pentagon and the White House or some military targets, I would have no problem defending him; but then he CHOSE to hit the Imperialist/Capitalist icon (WTO), making him another low life like Geroge W.M. Bush Junior*. There were WAY MORE innocent civilians in those 2 towers; but to say that ALL THOSE who worked there were innocent civilians would be plain naive.
* Sorry, I do NOT have one single bit of respect for this warmonger. I only respect respectable people. It doesn't matter if I am American or if he is the President of the day. (To be fair, Saddam Hussein is equally ridiculous.)