Out of interest why are you dismissing this without argument ? Only playing devil's advocate as holidaying on the continent in the summer and driving through France, Belgium, Netherlands I was struck how so relatively underpopulated they were compared to the UK. Didn't get into any heavy traffic all the time I was there, shopping in supermarkets was so stress free, no packed aisles. Trains were quiet, could always get a seat even at rush hour. Don't you think it's a reasonable thing to question, as a small island with limited space for expansion of infrastructure, can we realistically sustain net immigration to the tune of the population size of Liverpool ( thankfully not scousers), every year ?