Europe’s first major refugee crisis was the mass exodus of panicking Belgians in August/September 1914. My wife’s late grandmother, then a teenager, was among the human tide. She washed up in Brighton, on the other side of the Channel, and she recounted to me how, when she first heard the big guns on the Western Front, she thought it was distant thunder. Later, a Zeppelin flew low overhead on its way to London and she was afraid of the bombs. My late parents both lived through the London blitz. My father’s tenement building was destroyed by a landmine and he lost many of his friends. My mother’s family sheltered in dark, dank tunnels leading down to the Grand Union Canal and she suffered for the rest of her life from claustrophobia. Both recounted being transfixed with fear when the motors of V1 ‘doodlebugs’ cut out overhead; where would the bomb land? Tonight at a friend’s dinner table a fellow guest recounted how, whilst on a road holiday in Israel, she had lost her way somewhere in the north and overnighted in a hospitable kibbutz in the mountains. She was awoken during the night by what she thought was distant thunder. The next day the penny finally dropped when she was forcefully dragged into an air raid shelter. She went on to describe graphically the psychological effects of living in constant fear of bombardment. The process of European integration and of international cooperation more generally came into being to stop people having to suffer that sort of fear and worse. I understand that ‘the avoidance of war’ doesn’t seem particularly relevant to young Europeans who, in large part because of European integration, have never known conflict between European nations. But surely we shouldn’t abandon the explanation entirely. If young Europeans heard the lady telling her terrifying tale tonight, or my parents’ account of their experiences, or my wife’s grandmother’s, they would surely understand.