Why vaccine passports are causing chaos

MANY COUNTRIES did not require passports before the first world war. But as the conflict spread, states scrambled to introduce travel documents to help secure their borders. The result, after the armistice, was a bewildering smorgasbord of different information for different nationalities that could create chaos rather than clarity at border crossings. But returning to a world where people could travel freely across borders was by then unimaginable.

In 1920 the League of Nations stepped in. It designed a 32-page booklet with the country’s name on the cover and such basic personal information as place and date of birth. Some governments grumbled—France thought the booklet too expensive to print compared with its single sheet—and it took a few years for them to adapt. But today all passports follow the same format. Whether at Heathrow in Britain or Moshoeshoe I International in Lesotho, officials can glance at a passport and be fairly certain of its bearer’s travel privileges.