In your attempt to disprove the notion that Islam is a violent religion, your logic is flawed. I have not read the Koran, and don’t know what it specifically teaches or does not teach, but your argument that if the Koran advocated violence then 90% of the followers of Islam would therefore be radicals engaging in violence is wrong. Just as one possible illustration of why this is illogical: It is undisputed that Christianity teaches, among other things, that one should love one’s neighbor – now, aside from different people being able to interpret that in a multitude of different ways (more on that later), I think we can also pretty easily agree that 90% of Christians do not follow that precept all the time, nor do they make it the central goal of their lives. Does this disprove the notion that Christianity advocates love of one’s neighbor? Of course not.
Now, about interpretations. From what I have read, the debate about whether the Koran actually preaches that Muslims should kill infidels comes down to a matter of interpretation of a few specific passages. As former President Clinton demonstrated, the meanings of words can be parsed to such a degree as to make just about any interpretation possible (although not necessarily logically plausible). From what I can gather, the extremists have attached the “kill infidels via jihad” message to certain passages, and this is how they use Islam to advocate terrorism. Whether this is actually what the Koran teaches is a debate for Islam scholars, but there is definitely a substantial minority of Muslims that believes this is precisely what the Koran teaches. This is what we have to fight.
Finally, as to the idea that somehow Muslims would have been able to effectuate greater violence in the past if the Koran actually preached violence does not correspond to history or technology. Muslim nations engaged in wars in the past that they justified via religious means (as have Christians and probably every other large religion not founded in the last 200 years), and they prosecuted them to the extent technology allowed at the time, given transportation limitations and limitations on the amount of destruction that could be wrought with non-modern weaponry. In other words, they pillaged and destroyed as much as they could in the name of Allah. Muslim power peaked long before weapons of mass destruction entered the scene, and no Muslim country today has even the power to dominate the Middle East, much less to project power on a more global scale or to actually try to take on countries in Europe or the U.S. However, with the advent of chemical, biological and nuclear weapons, some of these states can now train and supply terrorist groups and attempt to plan attacks on Israel and the West, and evidence shows that countries such as Iran (a Muslim theocracy), Syria, Lybia, Algeria, Afghanistan and others have actively worked to further terrorist organizations and causes. Whether there is a causal link between the Islamic religion dominant in these countries has anything to do with this is not irrefutably established, but it at least provides strong circumstantial evidence to consider further investigation on the matter.
Personally, I think you are correct in drawing an analogy between Christianity, Judaism and Islam in that the teachings of each of these religions can be used to justify good and bad things, and have been used that way throughout history. The problem is that right now a large group of people believes that Islam justifies violent jihads against the West, Israel, and other “infidels.” The only way to fight this belief is to have other Islamic teachers preach the opposite interpretation and teach why it is the more correct interpretation. Unfortunately, there hasn’t been much vocal cooperation in this area, especially in the Middle East (and not even a lot in the U.S.A. from what I can see). And whether we convince them of the error of the violent interpretation or not, we had better do what it takes to stop them and protect our interests at home and abroad. 'Nuff said.