President Obama returns a greeting to Bun Rany, wife of Cambodian Prime Minister Hun Sen, (center) before a gala dinner in Phnom Penh on Monday. Mr. Obama was in Cambodia on the final leg of his three-country tour of Southeast Asia. Below: Hun Sen, here in 1996, examines a grenade launcher reportedly surrendered by Khmer Rouge rebels. Hun Sen’s reputation for violence owes much to the fact that he staged a 1997 coup against his own coalition government. (Associated Press)