Your belief that they are presumably stems from the common, but mistaken belief that immigration to the UK is predominantly if not wholly Muslim. Plenty of statistical evidence to show that is not the case. If you go to the Office for National Statistics website you will find immigration analysed year by year by country of origin rather than religion. While country of origin is obviously not an infallible guide, it's a pretty reliable pointer in the case of many countries. You can, for instance, be pretty sure that there won't be many muslims among the large numbers arriving here from Jamaica, South Africa, the Phillipines, or Australia - or indeed the USA. The most strking aspect, for me, of the immigration data is the sheer variety of countries of origin. Yes, there are predminantly Muslim countries there - but plenty of others also.