The chilling four-minute warning that would warn people of incoming missiles during the Cold War has been replaced by an app alert - with warnings that the survivors may truly "envy the dead." As the Doomsday Clock ticks closer to midnight than ever before, the reality of a nuclear strike on Britain has shifted from history books to a major concern as tensions continue to rise across the world . But gone are the days of hand-cranked sirens. Today, your only warning of an catastrophic event will