What Al-Qaida wanted to achieve was, disrupt the communications between the cultures, and they managed to do that.
Now, Muslims are unwelcome in Christian countries and Christians are afraid to go to Muslim countries. From what I see, they did what they wanted to do.
They were a couple of thousand people at the most, and they bent the whole world to the way they wanted. That I call "influence" whether you like it or not. If the world politicians weren't so hind-sighted with their own agenda, they would have easily defeated these couple of thousand people. But they opted to rant on the fear that this little klan created and just fueled the history long prejudices & fears.
Neo-cons used it to get hold on oil & control over south western & central asia.
EU members, especially France & Germany used it to leverage more power on Russia.
GB used it to get influence over US.
Israel used it to justify all they were doing. (Hey, what is what, Israel *is* occupying a territory since 1967. - All else are just details.)
Saudi Arabia used it to gain more control over world petrol market and use the opportunity of likely (and as time showed, definite) increase in petrol prices to get more influence on world economy.
Iran used it to increase her sphere of influence in middle east.
This list can be extended to hundreds of pages. The net result doesn't change:
1. US is trapped in Iraq & Afganistan & bleeding $80M/hr there. (figure might have changed since last I checked)
2. Net result of wars is a total collapse of US & world capitalist economy, resulting net gain on only totalitarian regimes like China & Iran.
3. Fear pumped by the west to their communities is resulting in fear & hatred against Muslims. (Which are about 1.5 B population on the world)
4. Hatred pumped by the west to their communities as west is resulting in sustained support to Al-Qaida, although US led operations against them took down many of the head figures, they recruit faster.
5. We have to face "security measures" stricter & stricter everyday that we practically won't be able to go any distance farther than a driving distance.
Sorry, this is a Tech site, but my post's also on topic.