If you were from another planet without any political biases, you would probably agree that, objectively, skilled immigration from people who will contribute economically and socially is good, but unskilled immigration from people who will not contribute economically and socially is bad, especially when resources in a country are limited.
So why do some on the left still attack those calling for restrictions on immigration or criticising it in any way? Just watch any Question Time debate - as soon as immigration restrictions are brought up, the left-wing panel members will 1) bang on about how immigration has benefitted the country, 2) warn against creating a climate of anti-immigrant feeling and fuelling UKIP, without actually addressing the point (no matter how sensible). Also, what about the furore over Labour's "controls on immigration" mug - what was wrong with that exactly?
It feels ridiculous that we are still at the point where it's considered taboo, by certain sections of the left, to be anything put pro-unrestricted immigration, even when the sensible approach is to restrict immigration based on the needs of the economy and who can benefit the country.
Yes, the far-right have at times poisoned the immigration debate, but that is no excuse for maintaining this nonsensical, rigid stance.