In my writing on this topic I shall be making some criticisms of Islam, and I believe that they are criticisms of Islam as such. In other words they are not criticisms that can be bracketed off as, in fact, criticisms of 'Islamism' or 'Islamic fundamentalism'. To be clear, and for the record, I shall also be praising Islam in significant ways before I finish – I do believe Islam holds up a mirror to the Modern West, and the reflection is not good.
(A technical philosophical note – I come at these questions from within the Western Christian tradition and, following MacIntyre and Wittgenstein, I do not think such traditions can be argued for from a place outside of any tradition. That's the Modern fallacy, which has led us into our present darkness. No, the contest between traditions has to be about which tradition has the resources to enable it to develop and respond to challenges as time goes on. I intend to challenge Islam as a tradition – and invite a response to that challenge. That is what dialogue is. There will be much more on this later on.)
There is in philosophical argumentation a fallacy that is known as the 'no true Scotsman fallacy'. It is a fallacy that often seems to be deployed when a Muslim does something outrageous, normally something involving hideous violence. Those who wish to defend Islam from association with the outrageous say things like “We continue to resist all attempts to associate our communities with the hate filled acts of any minority who claim falsely to represent us.”
I'm not a Muslim, I'm an outsider, but two things strike me. The first is that when, in their actions and in their writings, those who perpetrate atrocities say that they are Muslim and say that they are doing such things in accordance with their religious belief – and literally give the chapters and verses from the Koran which are used to justify their actions – I do not have the authority to disagree with them. To put the same point from the other end: if someone is prepared to die for their religious beliefs, I think that it is reasonable to think that those beliefs are indeed their religious beliefs. Which leads to the second thing – if such an action is not truly Islamic then there needs to be much clearer differentiation between the different forms of Islam. There needs to be a much greater witness and salience of that witness within the West. What we have instead is the march of hundreds of thousands in solidarity with genocidal terror. It's not reassuring.
Let me provide an analogy. Imagine someone who knows nothing about sport (difficult I know). They attend a match and see men running around chasing a leather object filled with air, one team contesting against another. The watcher comments 'oh, that's what is called football' – but is then rebuked by another witness who exclaims, 'NO it's not FOOTBALL, it's RUGBY!' Or it's Australian rules, or the NFL in the United States. My point is that the differences may be deeply significant – there truly is a difference between rugby and soccer1 – but to an outsider it all looks pretty much the same sort of thing.
If Islam is not essentially about violence and subjugation – and my argument in this writing is that, if that is not of its very essence then, at the very least, it lacks the resources from within itself to withstand that interpretation, and to stop people from acting on that interpretation – then we need to see much more differentiation. We need to see a much more radically gracious Islam. In a way I am asking for an English Islam, one that can coexist over a long period of time with different faiths in our common land. I believe that there are Islamic resources that can be drawn upon to build such a thing (I'm thinking of something like this) – but at the moment, what outsiders see are Muslims shouting 'Allahu Akhbar' as they indulge in sacred violence.
Those who follow the NFL might think that what they follow is real football – but it's not what the world thinks of, when they think of football.
Soccer is, of course, originally the English term for the sport, in distinction to rugger.
If you look at Osama bin Laden's Letter to America it has a number of direct quotes from the Koran calling for war and vengeance against unbelievers - and, as you say, there has been no outcry from the Islamic community at large protesting these alleged distortions of Islam.
It seems to me that any real Christian opposition to Islam must include statements, made in the right place, and in the right way, and at the right time, stating that Islam is not a true book of God, and Mohammed does not show the way to God. Of course that, if well known, would be met with violence, and then the Christians would be accused of stirring up hatred. In many cases it would even bring about legal sanctions not against the people who reacted violently, but against the people who offered simple statements of belief.
The whole system of freedom of religion in the West was designed with Catholics, Protestants, Jews, and various secular philosophies in mind. It was not designed for a religion that deliberately seeks to silence authentic debate.