Islam in our backyard

I have been reading Tony Payne's book, Islam in our Backyard. It has got me thinking about a few things that I've outlined below. Note that this is a summary of my thoughts in relation to his book and not a summary of the book itself.

Also, please do realise that I have enormous respect for Islam. I have many Muslim friends, and have both enjoyed their company and learned a great deal about life and God from our discussions. The following is not in any way a critique of Islam - or Muslims - but rather my thoughts in response to a book.

• A core principle of Islam is the union of church and state. This is irreconcilably opposed to the liberal democratic notion of separation of Church and state. If this is the case, could Islam's teachings be considered as treason?
• We live in a society that favors conformity and pluralism over truth and discussion. Yet is really being respectful to other people to leave them in ignorance. Surely it is more arrogant to dust something under the carpet than it is to discuss something in the open?
• Evangelicals will compare Islam and Christianity. Payne highlights that Islam teaches that Christ was not crucified; Christianity teaches that he was. This was an historical event, with a true answer - either Christ was not crucified or he was not... there is no 'in between'. Note however that the truth of this event does not support the remainder of each's belief systems, rather that the truth would deny one of them. Payne argues that the support of the first century Jewish historian (Josephus) and an eminent Roman historian (Tacitus), in addition to the New Testament provide better evidence for the Christian perspective. And when compared Payne's suggestion that Islam believes that he wasn't based almost purely upon Mohammed being divinely inspired to such an outcome... I can see why. That said, I would like to better learn the Muslim response to such assertions.
  
  There is some room for both being true, but far as I can see it, that relies upon the conspiratorial sounding notion of Jesus being drugged and seeming to have died.
  

Reading this book has led me to acknowledge better that there are some fundamental conflicts... and turning a blind eye to those differences may yet yield dire consequences.

Or not.