Yochi Dreazen, one of the best military correspondents in the business, has a fascinating dispatch from Afghanistan in the Wall Street Journal, in which he reports on the difficulties that U.S. forces have encountered with locally hired security guards. There have been instances of these guards firing on U.S. units and even when they’re not actively hostile it’s often hard to tell them apart from the insurgents.

This is the flip side of the problems experienced in Iraq, where U.S. forces and their contractors relied in large part on foreign security contractors, of which Blackwater was the most famous. Those companies created problems of their own, but their allegiances were seldom in question.