We should no-joke be thankful to Al Quaida: since 9/11 non-Muslim terrorism has pretty much completely disappeared as terrorist tactics have become synonymous with Sunni Muslim fundamentalist extremists.
Communists in all sorts of countries (Western Europe, South America, etc.), Basque, Irish, Tamil, Sikh, secular Palestinian, etc. nationalists, Shiite fundamentalists, radical environmentalists and animal rights activists, anti-abortion crusaders, far-right anti-government militia types... before 9/11 all these and more used terrorist tactics with no sign of letting up. On 9/12 it was obvious to all that the gig was up.