People think that combating terrorism, or Islamism is about fighting the benighted Oriental. This couldn't be further from the truth. The threat from Islamic radicalism and Islamic violence is quite adaptive. They adapt to their cultures (if they are migrants) and they adapt to western strategies to combat them. Several recent articles have articulated this quite well:
1) How (Not) To Spot a Terrorist, Foreign Policy.
2) Stumbling Towards Eurabia, The Journal of International Security Studies.
Something important to understand is that the people who articulate Jihad are not robed bandits in the mountains of Afhanistan. Many are well read, affluent, intelligent, and live in the west. The man most influential in articulating the new Jihad is Mustafa bin Abd al-Qadir Setmariam Nasr (known by his pen names Abu Musab al-Suri and Umar abd al-Hakim).
Al-Suri was born in 1958 in Syria and was a prominent member of the Muslim Brotherhood there. He actively participated in the planning and training of the MB in Syria. He founded a militant off shoot of the MB called "The Fighting Vanguard" (al-Tala'iah al-Muqatilah) When the Assad regime finally crushed an MB inspired uprising in Hamma, killing 10,000-30,000 there. This destroyed the Syrian MB (then based in Baghdad) but galvanized al-Suri's will and determination.
He is a veteran of the Afghan Jihad where he honed his military skills (1987-1992). In 1988 he gained Spanish citizenship when he married Elena Moreno (reportedly out of genuine love and passion).
His most prominent and copious work is Da'wat al-muqawamah al-islamiyya al-'alamiyyah ('The Call for an International Islamic Resistance'). This has been a widely read and extremely popular work. He has written another work which indicates his willingness to learn from past experience, al-thawra al-islamiyyah al-jihadiyya fi suria - alam wa amal (The Syrian Islamic Jihadist Revolt, Pains and Hopes). This is a summary of his experience of the uprising with a view to taking lessons from the experience.
Al-Suri's new ideology is far more rational than other radicals, in his recent works he has advocated a break from the ideology of direct confrontation and the establishment of a Nizam, la tanzim (A system, not an organization). This was developed in the face of western intelligence organizations becoming more competent at infiltrating terror cells. In such a formulation the days of linked and organized jihad is over. It would consist of a series of unconnected, loosely organized, ultra radical, ultra violent terror cells. We have seen the establishment of such a cell in the Harbi format in France, when approached by law enforcement the group detonated a bomb in their apartment killing themselves to avoid capture.
Combine this loose organization with the Harbi doctrine of finding what is prohibited (drinking, sex, pork, etc...) now permissible in order to blend in to the local society. This renders these groups much more impregnable with regards to intelligence and counter-terrorism.
Take this and add in the fact that 50% of German Muslims believe that those killed fighting non-believers go to paradise, and 25% that say they would participate in armed struggle against non-believers, and you have yourself quite a problem. Being that 44% of German Muslims are fundamentalist (See Bassam Tibi's work on the matter), at the very least these people will be very reticent to turn over fellow Muslims who are engaged in the activities that al-Suri has outlined. Now we have a group adapting to blend in and carry out far deadlier attacks, combined with a highly radicalized local population. This is a recipe for disaster.