itwbennett writes "In the aftermath of the failed Christmas Day terrorist attack, full body scanning technologies such as millimeter wave and backscatter are regaining popularity, writes blogger Steven J. Vaughan-Nichols in a recent post. But, he asks, do they really work? The TSA seems to think so. It has just issued a contract to purchase more millimeter wave scanners from L3 Communications. Michael Chertoff, the former homeland security secretary, told the New York Times that if these scanners had been in place, they would have caught the would-be bomber. Ben Wallace, the Conservative Member of Parliament in the United Kingdom, disagrees, saying that the technologies can't detect the kind of low-density explosive that the would-be terrorist tried to use on December 25th."