Why?

[Franconicus]

I know in the 30ies when the Nazis buiolt their SA gangs to fight the communists and socialists they told the young men horror stories about their enemies. What they would do if they could, how they rape women, torture their prisoners ... . After that those men were so scared that they were happy to be in a SA brigade and willing to do to their enemies exactly the same things they heard before. Same thing happened over and over, for example in Bosnia. So the motivation is fear, caused by propaganda

[TonkaToys]

[BrainDump]
Indoctrination of extreme belief and misrepresentation of the enemy seems to be the principal way of creating terrorists.
The extension of hate to encompass an entire nation, instead of just targetting the leaders or military bodies of that state, means that the people of that nation become the perceived enemy.
The phrase that Blair used yesterday, "way of life" , is telling too; the extremist sees one culture as a threat to their way of life and is therefore self-justified to try to destroy the other culture.
The fact that religious self-sacrifice is seen as holy and a way to become a martyr make it easier to justify hurting others as long as you too are hurt in the name of your beliefs.
The anonymity of the people you are hurting must make it easier; would it be so easy to blow yourself up in a crowded street if you knew that your sister's husband was there? Wouldn't you think about the consequences to your family?
The cult of personality must have an effect; you idolise a teacher, and that teacher says you will be heroic if you commit a crime.
[/BrainDump]