Among the flaws in this argument are the misguided ideas that borders rather than German militarism caused the First World War (among a range of complex factors) and that anything but Nazi aggression caused the Second World War. It might be convenient for some, not least some Germans, to adopt alternative explanations, but blaming borders for the wars of the twentieth century is like blaming cars for all traffic accidents. If borders can sometimes cause conflict it does not follow that without borders the world would be without conflict. After all, before the wars of the nation states in Europe, the continent was wracked by wars of religion.

But the flaws in the Schengen Agreement lay not only in the presumptions it made about history. The terrible flaw in Schengen was the way in which its principles were practised. For instance, although member states committed to cooperate in policing the outer borders of the continent, in reality the task was left to the front-line states. Throughout the late 1990s and 2000s Italy, Spain and Greece were abandoned to deal with the inflow alone. Even after the creation of the EU border-force Frontex in 2004, the southern states continued to bear the burden. As an exasperated Italian Interior Minister, Angelino Alfano, had to remind his counterparts during the Lampedusa crisis in 2014, ‘The Mediterranean border is a European border.’

But it was not only the burden of policing the borders for the whole continent that stretched the Mediterranean countries during this period. These were also the three (to date) iterations of the Dublin Regulation on asylum, an EU-wide agreement that was instituted from the 1990s onwards. The aim of the several versions of the Dublin Regulation was to ensure that the EU member state in which a migrant requested asylum was the state that was legally compelled to process that application. In theory it was meant to prevent multiple applications by migrants or their shuttlecocking between states. In practice the Dublin Regulation put the onus on the southern states. Given that the boatloads of people with or without documentation were arriving to claim asylum in Italy and Greece rather than Holland or Germany, the Dublin Regulation gave countries like Italy and Greece only a few potential options.