It's been 26 years since I last remember police cars speeding up my road to the riots at the Broadwater Farm estate in North London. Then - just like last night - a policing incident had been the spark that ignited latent social and political tensions that had been building for years. The previous Tottenham riot wasn't an isolated incident: prior to that there had been riots in Brixton in South London, Toxteth in Liverpool, and Handsworth in Birmingham. And last night the same scenes returned to my beloved city.