When soldiers are teamed with robots, the human need to interfere may negate the benefits of robotic assistance, a new US military project has discovered. But letting military artificial intelligence proceed without human supervision raises troubling ethical questions.

The System-of-Systems Enhanced Small Unit (SESU) project foresees a team of around 200 to 300 soldiers augmented with swarms of small drones and robotic ground vehicles. The lightly equipped unit would fight in zones where the enemy …