Why ask only of Asians? ok, I get the point of suicide bombers etc but really, that has nothing to do with the question.
So are you asking, do we want people who have sadly happened upon a bad name for themselves due to a distructive sect ientering the UK or, are you asking Do we want people from all over the world to come to the UK to live, work and contribute to society like the rest of us?
Either way, who are we to judge? If you stop others from entering the country on the grounds of race then I think this would be a sad little part of the worldto live. Next we'll be stopping people crossing the borders and before you know it, we'll all have 3 heads, eleven toes and an uncle called Bertha!