Immediately after the riots of August 2011, David Cameron declared war on gangs. Heavy-handed enforcement tactics followed, and 200 gang leaders were arrested. It was a PR-driven, kneejerk response ? and it failed. A new report by the Centre for Social Justice concludes that the arrests led to further "chaos, anarchy and violence". Younger gang members stepped up to fill the power vacuum left by the arrests, and the result was frightening: think Lord of the Flies.