(By Christopher Swift, an adjunct professor of national security studies at the Georgetown University School of Foreign Service and a fellow at the University of Virginia's Center for National Security Law.) I've done fieldwork on the insurgency in Chechnya and Dagestan and have studied the war there for nearly 15 years. I've also interviewed several very prominent rebels. This would mark the first time Chechens have attacked any sort of U.S. target. Up until now their focus has been on Russia. This is a big deal. And it shows how the conflict in the Caucasus has metastasized ...