OXFORD – Just when it seemed that America’s “Homeland Security state” could not get more surreal, the United States Transportation Security Administration has rolled out a costly Scylla and Charybdis at major airports: either you accept dangerous doses of radiation and high-resolution imaging of your naked body, or, worried about the health risks of cumulative radiation, you opt out of the new full-body x-ray machines (rapidly dubbed “porno-scanners”).