Christina Schmid, Widow of Staff Sgt Olaf Schmid, Royal Logistic Corps

More than 300 British servicemen have been killed in Afghanistan. For families, friends and comrades that's an unremitting toll of pain and loss. Most grieve far from the public gaze, but not Christina Schmid. Her husband, Oz, was one of the British army's top bomb disposal experts. He was killed in action in October 2009 and was posthumously awarded the George Cross for his outstanding courage. Christina Schmid has since been asking questions about the way Britain treats the soldiers it puts in harm's way. HARDtalk's Stephen Sackur asks what lies behind her campaigning zeal.