Tran Trong Duyet - a sprightly retiree and amateur ballroom dancer - must rank as one of John McCain's more unlikely supporters.Four decades ago, during the Vietnam war, Mr Duyet was in charge of the notorious Hoa Lo prison - the place where Mr McCain says he was brutally beaten and tortured during five-and-a-half years as an American prisoner of war. "McCain is my friend," said 75-year-old Mr Duyet as he feeds the caged birds he now keeps in his garden in this coastal city. "If I was American, I would vote for him." Informal chatsNavy pilot John McCain was...