It's a classic case of bolting the barn door after the horses are gone. Politicians are angry that the "crotch bomber" (who tried to blow up an airplane of Christmas day) got through airport security with his explosives undetected, and have demanded that full-body scanners be placed in all airports. So far, 19 U.S. airports are using the scanners, and the Transportation Security Administration (TSA) hopes to put hundreds more in airports across the country. Proponents of this technology argue that it's worth sacrificing privacy (and modesty) for safety. But in their rush to do something policymakers be ignoring five big problems with rolling out this technology: 1. Manufacturers aren't willing to fill orders. According to a spokesperson for Smiths Detection, a manufacturer of millimeter-wave body scanners, the