After two men hacked another to death on a London street, one of them made a statement to an observer with a cell phone. "We swear by the Almighty Allah we will never stop fighting you until you leave us alone. We must fight them as they fight us, an eye for an eye, a tooth for a tooth." Prime Minister David Cameron, who returned from a visit to France to address the incident, assured citizens of heightened police security but encourage that "one of the best ways of defeating terrorism is to go about our normal lives." Kim Sengupta is defense and diplomatic correspondent for The Independent.