What does a terrorist or insurgent look like? When asked, most people will respond with a variant of one of the following: 1) the old 'They're Arabs, Muslims' or 2) the politically correct 'They can be anyone of any color of any religion of any sex', etc, etc. Both answers are wrong. We know that not all terrorists are Arabs or Muslims. Even people who make this statement know it is incorrect. However, the politically correct version that 'it can be anyone' is equally, if not more false.
A major but oft-overlooked cause of Terrorism is idleness and unemployment in third world countries where the majority of the population is under thirty years old. That is a severe oversimplification, but a good starting point. If the United States were to descend to the level of a third world country, the young (and some not-so-young) people in our neighborhoods could easily become insurgents or terrorists. Think of a lot of uneducated, unemployed, idle youth and add to it something which they can line up or unite against, such as a foreign invader that supposedly seeks to destroy their way of life. There are many people in this country today who are easily convinced of the same thing already.
Think if you were a young man, had less than a high school diploma, and were un- or underemployed. What would happen if a well-spoken, educated, older man came to you and convinced you America was to blame for these woes and spoke of friendship, brotherhood, equality, justice, revenge, and a little adventure. It would be a chance to make a mark on the world and to gain respect. The only recruting conditions this man needs are disaffected youth, an enemy to rail against, and a program to indoctrinate. This is how much of terrorist activity begins.
Terrorism in our minds these days is inseparably connected with Islam. This is misleading. While the many terror attacks against America and its allies in the last decade have been perpetrated by Muslims, Islam is simply the tool used by a hierarchy of political Islamists to indocrinate the disaffected youth in their countries with the hope of placing them or keeping them and their ideas in power. These political Islamists use a hardline version of the religion to draw a line between themselves as 'true' believers and others as non-believers, a strong argument in the muslim world. Islam is not the reason terrorists exist; it is a tool used to create them. The religion itself could be replaced by some other idea just as powerful. If the same socio-economic conditions existed in America or Europe today, Christianity could be used to the same effect.
Muslims see each other as brothers and find it difficult to work against a fellow Muslim, even if they were born in the U.S. or live or were educated in the west and even where they believe themselves that terrorism is wrong and hurts other Muslims. This is why the West has such troubles finding Arabic speakers willing to work in the military and intelligence communities. Islam is not a religion that preaches terrorism; it is a religion that preaches brotherhood within a community of believers. This fact is turned against the community of believers by Political Islamists using it to keep decent Muslims quiet and turn disaffected youth into a tool to put or keep them in power. There is not a 'clash of civilisations', but simply politicians using rhetoric, suspicion, youth, and anger for political gain. It kind of sounds familiar in the end, doesn't it?