There is a new kind of tree growing out west. Botanists have yet to decide how to classify it. Politicians and the major media seem to want to ignore it. The sight of one is enough to make weathered old cowboys who thought they'd seen everything in life break down and cry. Not many people have seen these trees, for they grow in out of the way places in the southwest desert along the border with Mexico. But those who have seen them are haunted by the memory. In an era of free trade agreements and politically correct euphemisms for...