Asked to compare eight difficult periods of the nation’s history, 46 percent of the 354 professors who responded to a nationwide survey agreed the current era was the least trying. The Civil War, 55 percent said, was the toughest. Researchers at the Siena Research Institute of Siena College came up with the survey after hearing students comment they felt today’s era was one of the most trying in America’s history. ”It’s an issue of perspective,” said Thomas Kelly, a professor emeritus of history and American studies at Siena who helped conduct the survey, which was released Thursday. ”With very few exceptions most generations have confronted enormous kinds of problems and have to greater or lesser degrees coped,” he said. Next to the Civil War Ã¢â?¬â?? which threatened the nation’s very existence and cost the lives of more than 600,000 people Ã¢â?¬â?? the poll found the Revolutionary War and the Great Depression to be the most trying, followed by Vietnam and the Cultural Revolution, World War II, the Cold War, World War I and today.