Well we are dealing with it quite well, actually, most of the Islamic extremists and their networks have been or in the process of being dismantled.
Jailing those who encourage subversion and terrorism such as Abu Hamza al-Mazri. Other radical Muslims such as Omar Bakri Mohammed, have fled the country.
While prior to Sept 11th we may have allowed even encouraged some groups because of the Cold war and they made great anti Communist re Soviet Occupation Afghanistan, things are changing now.
Hopefully they won't shift to a guerilla war there.