i am not convinced they would, why are some young men tempted, or do go and fight for a country they have never visited, perhaps their parents, even Grand parent homeland. We are a much more mixed society than before, people from all over the world have settled here, or live here for a time, are they likely to fight for Britain if their native country was under threat, particularly from the west.
If you look at how some of our society is divided i can't see it happening. Where once we had a common bond, and a common language, that is not necessarily the case now. Lets hope it doesn't come to that, perhaps we should be more concerned of our home grown terrorists, disaffected, easily swayed young men, ready to take up a cause...