ON AUGUST 1st the UN's Convention on Cluster Munitions, banning the manufacture, use and stockpiling of cluster munitions came into force. The UN estimates that 98% of victims of cluster munitions, explosive weapons that scatter bomblets across a wide area, are civilians. The convention has been signed by 107 governments and ratified by 37. Of the 87 countries which have had stockpiles of cluster weapons at some point, 38 are signatories. But many producers and stockpilers of cluster bombs (including China, Russia and the United States) decided not to sign the convention.