D'Souza picked out all the criticisms that came from the left, but Ive read just as many from the right. His 'blame America' idea, and that we should just ally with the Islam isnt playing well with either wing.
That's a very good point. What D'Souza is saying is that we are demanding changes in traditional Muslim culture. D'Souza points out that they resent it, and I think correctly that it's what motivates the fighting. I haven't finished his book yet, so forgive me if this turns out to be off-base, but I think that a lot of critics have interpreted his explanation of Muslim resentment as a defense of it.
In short, the Muslim radicals are afraid that we'll win the fight without a shot and hence have started shooting; that unless they turn the world to Shari'a we will ineluctably turn it to both the good parts of Western culture and the bad. It's only on our side of the fence that we differentiate the good from the bad - as I tried to say above, we social conservatives tend to promote the emancipation of women and divorce it from the promotion of abortion. In our eyes the two issues aren't the same. In the eyes of the Muslims they are. And in the eyes of many on the Left they are as well. That's just my guess at explaining what you've pointed out.