Mark Steyn notes a Church of England editorial according to which Islam is gaining ground rapidly enough in England that it will soon be able to claim that England is religiously a Muslim nation (it’s not at all clear what the threshold Islam will pass in 30 years is). He calls this national suicide.
Leaving aside the Islamophobia, it’s quite clear that England will not identify as a Muslim nation anytime in the future. Three possibilities suggest themselves, none of which follow Steyn’s scenario. First, people might actually become more Christian in England, as a sort of identity politics, reacting to the growing number of Muslims. Christian church going might become a way of asserting one’s difference from them. I doubt this is likely, but this kind of reaction is a real phenomenon. Second, people might get more aggressively secular. Many secular folk regard the church as fundamentally harmless, having grown up within it or nearby it, but never having felt much impact from it. However, confronted by an assertive and foreign religious group, they might begin to press the claim that religion has little place in society. This is what has happened in France. As their example shows, it may not be a benign development, but it also is not establishing Islam. Third, Islam might be domesticated, with the conservative aspects of its religion practice diminishing in visibility and importance. In light of that development people might happily live and let live. That this domestication is not happening is the worry that possesses Steyn et. al.