The dreariest aspect of human nature, as far as I've seen, is perfectly illustrated by the fact that the world's fastest-growing religion is nothing more than a very effective rallying cry for the release of pent-up aggression--both on a personal scale as well as on a social one.
This thing will come to a head eventually, and it will happen in a way that history has not yet foreshadowed. Modern weapons can alter the world in minutes. If Islam doesn't enlighten soon, and significantly, god will have a hell of a job sorting through all the newly-liberated souls.
On a historical note, I'd like to say that religions going through periods of radicalism is nothing new. Christianity did a fair job of it as well, the difference is, that we're alive now, and we're seeing this now, and none of us has much perspective on what was happening centuries ago, when a whole different slew of whackos were killing in the name of god. There is fear and there is a willingness to tolerate radical Islam today. It comes from a lack of understanding of how far they will take things, from tolerance--which is becoming more and more popular in Western Society as of late--and most of all, from a strong interest in maintaining a status quo which very much favors our way of life.
But the Muslims, today, are planting the seeds of their own demise. With every act of hatred, intolerance and over-zealous insanity, they are planting an innate understanding of their true nature in generations to come. Forget the history and the text-books. The true nature of which I speak is the opposite of all this 'religion of peace' nonesense. It is an indoctrination of inflexability. It is an indoctrination of obsessive fixation. It is an indoctrination of abuse, and if this persists, and does not end with a rash of fusion reactions here and abroad, the backlash will come.