London is a World City, so you get all sorts walking about there, of all nationalities and religions. You won't see a single Burkha where I live, or hardly any foreigners at all, until the Poles started arriving a couple of years ago and even then there are relatively few of them.
It's important to remember that out of a population of 60 million, we have only just over 2 million Muslims. We DO need to root out the radical communities, though, most definitely!
The problem is you need 30.1 million of the 60 million to vote for a leader who will kick them out and then you will need 10 million to kick out the 2 million. A tall order.