Pirates in the ancient world were both an endemic menace and a usefully unspecific figure of fear, not far different from the modern ‘terrorist’ – including anything from the navy of a rogue state to small-time human traffickers.

Thanks to the astute, if mercurial, diplomacy of John Adams, such an invasion never happened. When the president sent two envoys to France that October, without consulting his cabinet first, Washington was beset by serious doubts. “I was surprised at the measure, how much more so at the manner of it?” he told Hamilton. “This business seems to have

they committed most of those acts in international waters, where legal jurisdictions were by definition blurry. Declaring that pirates were “enemies of all mankind” gave local authorities on land the legal justification to try them for their crimes, even if those crimes had taken place on the other side of the world.