Norway recently charged three Moslem immigrants (from China, Uzbekistan and Iraq) with plotting terrorist attacks. These three were similar to others recently arrested in Britain and the United States. That is, they fled to the West, were granted asylum, and then were seduced by Internet based Islamic radical groups to seek revenge on the West for its war on Moslems. Counter-terrorism officials in Europe believe there are thousands of such men (and a few women) who have been stirred up by events in Iraq and Afghanistan, where Western troops are fighting Islamic terrorists.
The cause of this Islamic radicalism is the failure of Islamic cultures to keep up with the West in terms of education, economic growth, scientific progress and good government. The Islamic radicals have, for over half a century, been trying to address the deficiencies in Islamic states by trying to overthrow their corrupt governments and replace them with religious dictatorships, run by clerics. The three such Islamic states that were established (Iran, Afghanistan and Sudan) have all failed. Iran is crippled by corruption (among the ruling clerics) and popular discontent. The Islamic government in Afghanistan was beset by rebellion, and overthrown by the rebels in 2001. Sudan did not allow the clerics to be in charge, but the country is torn by civil war, and effectively partitioned.
Algeria defeated its Islamic rebels after a ten years of bloodshed in the 1990s. Same in Egypt, and the Palestinians are split by Islamic and secular factions. Pakistan is fighting a war against its Islamic radicals, while Somali attempts to reform its secular government are hampered by Islamic radical factions (who fight each other, as well as secular and Moslem militias).
One of the main problems encountered in Islamic nations is a refusal to accept responsibility for many of their internal problems, and a fondness for blaming distant, and non-Moslem, foreigners for everything that is bad. Thus the popularity of waging terrorism campaigns in the West. This approach was first proposed by al Qaeda in the 1990s, largely because al Qaeda believed that rebellion from within would never overthrow the secular dictatorships and monarchies so common in the Islamic world. All this is complicated by many political (usually leftist) factions in the West who refuse to recognize the very different mindset in the Islamic world. There, hatred of non-Moslems, especially Jews, is widely accepted. Thus many Moslems, including a lot who have been educated in the West, still believe that the September 11, 2001 attacks were actually carried out by Israel, and made to look like Moslems were actually responsible. These bizarre, and self-destructive, attitudes are openly displayed on web sites in Moslem nations, even on sites that are in English.
The Islamic terrorists are hampered by many of their own beliefs. Their hostility to Western education leads to a lack of useful skills in the ranks. Their belief that God is on their side also leads to dumb moves and poor planning in general. Islamic radicalism is opposed by many Moslems, generally the more literate and able people. But because of the religious angle, it's difficult to organize effective opposition to Islamic radicals within the Moslem community.
Counter-terrorism officials in the West understand whats going on, and urge their political leaders to do more to convince Moslem migrants to adopt Western attitudes towards education, democracy and the importance of respecting the laws and customs of the nations that have granted them asylum. For many decades, it was fashionable to allow these Moslem migrants to maintain their alien, and destructive, customs. That multi-cultural approach is largely (but not universally) discredited, and recognized as the cause of Islamic radicalism surviving among these Moslem migrants.