The American government has hit on the perfect war to inspire and unite its people against an outside foe so they don't look to closely at their own society. Also, a war they can use to demonise anyone who disagrees with them, or their policies.
You cannot win a war against Terrorism because terrorists are more than willing to die for their cause. You cannot beat terrorism with weapons, only with peace.
The goal of the 9/11 Terrorists has been achieved, many many times over, through the actions of the united states and its allies, including the country I was born in and the country I live in. Terrorists do not only want to scare and terrify people, but to inspire others and cause reactions in their own people to aspire to the same ideals and goals. This is done, most effectively, when your target responds with overwhelming force and violates it's own principles, making itself an easy target for blame.
The only way to beat Terrorists is to stop screaming for blood and start being the "better man". Meetings, diplomacy, compromise.. but the United States, already torn and divided internally, seems to consider compromise a dirty word... and has been so long without truly knowing what peace is, that it derives it's strength and unity more from the fear of outside threats than any sense of community and shared culture.