Islam versus Europe

First, the immigration cap only applies to the inflow of non-European Union residents. And it doesn't so far apply to non-EU student immigrants, or those whose eligibility is based on family ties. It only applies to labour applications, themselves only 20% of the non-EU inflow – which in turn is a drop in the ocean of total inflow. These working visas are estimated to account for 5% of net migration, and that is a generous estimate: some studies put them at 1%. Then there are the exemptions: intercompany transfers are exempt, and those are historically the biggest share of workforce immigration from outside Europe.

OK, let's say they ended all exemptions. Even if they shut down any movement at all from the labour force outside the EU, it wouldn't produce a fall in net migration that would hit even tens of thousands. This cohort is just too small, and capping it changes nothing unless you count the vexation to the people so arbitrarily refused entry and the reassurance to a few Ukip voters who couldn't be arsed to look at the figures.