Cluster bombs are small anti-personal munitions, rather like handgrenades, meant to be dropped from airplanes or helicopters or shot from ground-based weapons. In theory, they are effective weapons of war because they increase the likelihood of the person using them killing the target he aims at: in reality, up to forty percent of the bombs don't detonate on impact, leaving a battlefield strewn with small, unstable and deadly explosives which present all the charms of land mines.

The Times has a good piece about the hazards unexploded cluster bombs are presenting to civilians in southern Lebanon, where more than 100,000 unexploded bombs remain. The accompanying video is really worth watching.

Activists are working to ban cluster munitions. Like the campaign to ban landmines, this is a worldchanging effort, as cheap anti-personal weapons destroy lives, wreck economies and keep conflict areas unstable long after the fighting has ended.