A FORMER NAVY SEAL who shot Osama bin Laden and wrote a bestselling book about the raid is now the subject of a widening federal criminal investigation into whether he used his position as an elite commando for personal profit while on active duty, according to two people familiar with the case. Matthew Bissonnette, the former SEAL and author of No Easy Day, a firsthand account of the 2011 bin Laden operation, had already been under investigation by both the Justice Department and the Navy for revealing classified information. The two people familiar with the probe said the current investigation,...