The bewildering array of drone technology available to modern‑day battlefield commanders is certainly a far cry from the cumbersome structure the Austrians used to attack Venice on August 22, 1849 – the earliest recorded use of a UAV in combat. On that occasion, balloons fitted with bombs were directed towards La Serenissima, where they were set on fire by means of an electro-magnetic charge passed through a long copper wire, causing the explosives to fall on the city below.

The balloons proved ineffective as, more often than not, they were caught by a change of wind and blown back over Austrian lines. But had they been successful, the human rights lobby would no doubt have been queuing up to bring Emperor Franz Joseph I before the 19th-century equivalent of the International Criminal Court for war crimes.

In the modern age, though, it seems the drones are at risk of becoming victims of their own success, as human rights campaigners intensify their efforts to limit their use in targeting al-Qaeda terror cells.