SIX YEARS ago the British Army’s 3rd Division, the country’s flagship fighting force, visited North Carolina for an exercise. It won battles thanks to strikes deep behind enemy lines. But those strikes used munitions that the British Army did not have and was barred, by treaty, from owning. Instead, a US Army corps, firing dual-purpose improved conventional munitions (DPICMs)—commonly known as cluster munitions—“saved the day time and again”, recalled John Mead, then a brigadier. “They were, and are, a game-changer.”