Be honest - the same people have asked me the same question numerous times on Mudcat, and I HAVE answered frankly giving several reasons...trying to have a multiple number of cultures living under the one state law will always be problematic (and even New Labour - having strongly promoted immigration/the multicultural state for nearly a decade - have just begun to lean this way with English tests, etc., for potential immigrants); ethnic conflict; it's much more difficult for tourists to terrorise; when people lose their own culture, society suffers; 50 million is too many people for the area of land called England; etc.