POLITICS, like fall foliage, turns faster in Vermont. The state was out front opposing slavery and first to approve civil unions. And if the activists who met here last month succeed, the state will set another precedent: first to secede since 1861. No, this wasn’t a clandestine meeting of militants. It was a convention for Vermonters, held in the plush, gold-domed capitol. And its keynote — that separating from the United States is a just remedy for the federal government’s trampling of state sovereignty — is echoing beyond the snowcapped Green Mountains. From Hawaii to South Carolina, dozens of groups across America are promoting a similar cause. Their efforts aren’t politically popular — yet. But they are reviving one of the most passionate debates in U.S. history: Can a state legally secede? For the Second Vermont Republic (SVR), the group that hosted the convention, the answer is “yes.” To mine intellectual capital for these ideas, SVR has dug deep into what critics call the neo-Confederate vein of Southern ideology. The group has promoted the work of scholars affiliated with the League of the South, which advocates greater autonomy for the Southern states. One of them, Donald Livingston, a professor of philosophy at Atlanta’s Emory University, wrote a cover story — “What Is Secession?” — for the Vermont Commons newsletter, in which he philosophically defended the principle. The 15 states that left the Soviet Union beginning in 1991, Dr. Livingston says, show that secession can be a peaceful instrument to dissolve an empire that’s become dangerously large. “The public corporation known as the United States is too large,” he says. “It needs to be downsized like any other corporation.” Today, most experts say states have no legal right to secede. “To exercise the right of secession requires a violation of national law,” says Herman Belz, a professor of history at the University of Maryland. JOSH BUREK Christian Science Monitor