Flying out of Norfolk last week, the steel shank in my shoes set up the METAL detector.  Instead of checking whether I was carrying a gun, they swabbed my hands for explosive residue.  Flying out of San Francisco yesterday, the same steel shank in the same shoes did NOT set off the metal detector.  However, I forgot to remove a comb from my back pocket, and they decided America would be safer by swabbing my right hand, but not my left one.  Huh?

And, that makes sense because . . . ???