Looking out to sea from the Port of Dover, it is possible to discern the “melancholy, long, withdrawing roar” of the retreat by Britain from the civilised and humane treatment of migrants. Hundreds have crossed the English Channel in small boats this year, often no more than frail rubber dinghies with outboard motors, in a desperate effort to stand on British soil. The government increasingly sees it as its duty, doubtless presuming the backing of public opinion, to thwart them by any lawful means, including using the Royal Navy to intercept them. It has even contemplated opening concentration camps for them on remote Atlantic islands. Such an attitude is shameful and unworthy of the United Kingdom.

In order to qualify for the right to claim asylum, migrants have to be physically present on dry land. This is a peculiar quirk of international law that the UK, and many other countries, have ruthlessly exploited. The goal it sets for the authorities is to turn these boats back before they reach the shore. Halfway across the Channel they leave French territorial waters and become the UK’s responsibility.