One day he will be the head of Britain’s armed forces. But today Prince William took a big step forward in his own military training by graduating from the prestigious Sandhurst Academy. The future king, now an army officer, is off to pastures new to learn to be a troop commander. The presence of his girlfriend Kate Middleton at the parade ground was significant. It is the first time she has been Prince William’s guest at such a high-profile event, attended by senior royals. The prince’s father Prince Charles and step-mother the Duchess of Cornwall were there as was Queen Elizabeth. The gathering comes a day after a British police inquiry ruled Prince William’s mother, Diana, Princess of Wales, was not the victim of a murder plot.