[DemolitionRed]

But Britain and Northern Ireland never joined the Schengen agreement. We were one of the countries that opted out.

The countries who did join can opt out at any time, they don't need to leave the EU to do that. Germany and Austria have done just that since a record number of migrants have travelled there. France has re-imposed its border controls from time to time and so have the Dutch.

For the Brits, the one thing that benefits us from the Schengen agreement is rapid response when chasing criminals across borders.