Now TSA says X-ray detectors CAN detect shoe bombs, while Homeland Security says it isn't true

Nice. When first asked by AP the other day, no one disputed Homeland Security's study of last year that said X-ray machines at airports were insufficient for detecting explosives, including shoe bombs. Now the Transportation Security Agency is saying balderdash! Of course X-ray machines are good enough to detect shoe bombs! Uh huh. So I guess that means that Homeland Security's studies on how to defend America are worthless. Again, nice.

So which one is it? Are airport X-ray machines worthless for detecting bombs, or is the Homeland Security agency worthless?