FORT BENNING, Ga., April 5, 2010 – With four military retirements behind him, Army Col. (Dr.) William Bernhard says President John F. Kennedy's plea to the nation nearly 50 years ago inspires him to keep going. Army Col. (Dr.) William Bernhard is serving a voluntary rotation in Hohenfels, Germany. The 79-year-old flight surgeon, who has retired from the military four times, said this will be his last active-duty assignment. U.S. Army photo by Tiffany Nabors (Click photo for screen-resolution image);high-resolution image available. "JFK once said, 'Ask not what your country can do for you; ask what you can do for your...