What information do you have that tells us anything concrete about the "long-run" of Islamofascism that you can make so confident a statement?
Socialism and communism have killed millions of people and hindered the lives of billions in the last 100 years. Islamofascism hasn't even come close to the impact of socialism/communism. Sure, two huge buildings coming down are pretty dramatic but by no means would destroy the US. Push comes to shove we could blow up the entire middle east if we felt it necessary and not worry about it. The creeping socialism in the US at this point is almost impossible to stop and at some point will break this country.
Islamic facism is not limited in its scope to 9/11. Its impact is already well entrenched in much of the Middle East and Persia, not to mention some parts of Africa and the Far East. Its effects are only starting to be felt in Europe (Mohammed (and variants) was the #2 name in the UK last year. I believe it's #1 in Belgium.). IOW, 9/11 is not the definition of Islamofacism. It's only a symptom. If you talk to the people of the Sudan or Christians in Iran, you might have a different opinion of the effects of communism (a different manifestation of socialism, which you freely interchanged) vs. Islamofacism.