1 Answer

Religious ideology would be my choice.  Its a sad thing that there are actually people today in modern times that think they will go to heaven by killing innocent people.  They worst case of conditioning and indoctrination.  They are so deep into it that they believe it, so they act on their beliefs.   

Thise two boys in Boston I believe were driven by jehad and also morbid entertainment as proven by their actions right after the bombings by bragging about it, the license plate 'Terrorist !"  these are foolish fantasies, their fantasy was pushed by religious beliefs and became reality.  I believe the older brother was conditions, the younger brother was out for a night of morbid fun, not realizing how deadly his brother really was.  regardless, I don't want to humanize the younger brother, he should be locked up for life, although I doubt he would live a long life, someone will kill him for certain.  I do not think death penalty although i can't reason where there was a better case for the death penalty.   I am not convinced its the right thing to do, personally, I think prison life is worse than death, and we all die, some of us will die painfully, others will die peacefully.  If he gets the death sentance he will die most peacefully.  I don't think that is punishment enough since we all must go through the same thing sooner or later. Life in prison i think is best. 

But I digress.  

Certainly there's much negative information on the web and the weak minded would surely be affected by it.