Taking a step back, if we look at the origins of mankind we will see that we are by nature tribal animals. Therefore it follows that our natural instinct is to reject the interloper. A sketch from the likely lads has Terry complaining about Germans when he has returned from army service. By the end he has written off foreigners, non-Geordies, people from other streets and the next-door neighbours. We all have this natural tendency buried in us, but we are supposed to be civilised and should be repressing our feelings. We have been given the gift to think for ourselves and to overcome our nature in the cause of civilisation and humanity.
The bottom line is that racism or tribalism is uncivilised. As has been said by many on here and elsewhere, there are good and bad in all societies, so let's leave it there and move on.
Localised problems like overcrowding, competition for jobs, etc., may need to be sorted, but we need to try to be open, honest and fair, or we'll go nowhere.