The main difficulty of this psychological issue is that reasons of terrorism depend on many external causes. The main reason is religion. For example, Muslims believe hat dying in Jihad is very honest. So maybe we should look for reasons of such radical depending on religion. Some psychologists explain that when people have weak Ego, when they are not self-confident they unconsciously begin to look for some groups to join. Those groups may be of different types: It can be dependent on music style – rockers, rappers and so on, also those groups can be made by religious or social basis for example, Muslims, Christians, drug addicts or alcoholics. When people join any group they begin to feel stronger – this is the reason why they try to do everything for that group – they can even become a terrorists. Personally I support this idea.
However, it is said that psychological terrorism reasons can be explained as some combinations of traits, childhood events and some other factors. For example, extraversion + early death of parents + being poor. However, this theory isn’t finally proved. It is not valid yet because the same researches often give different results.
So finally, I can say that terrorism is one of those spheres where psychology can be improved. Perhaps after some time there will be some undeniable evidence about the reasons of this phenomenon. And let’s hope that soon some ways to deal with this problem will be found.