I live in the flat, scruffy desert of southwestern New Mexico, a half-hour from the Mexican border town of Palomas. There's been a war going on in Palomas for over two years. A dusty town of 5,000 people, Palomas has more murders per capita than any city in the world, some say. I talked recently to people who live there, mostly by going to little grocery stores. They estimated that 50 to 60 people have been murdered this year, though you'd never guess it if you just strolled through town. The violence has hardly affected either Columbus, N.M., five minutes from the border, or Deming, N.M., where I live. There's virtually no spillover. But it has deeply damaged the economy of Palomas, which partly depends on the dentists, oculists and pharmacists that have catered to Americans for years. Americans are staying away in droves. A couple of years ago,