Consider a father on his way to a TDY location. Family are there to see the father off on his flight. As they go through the checkpoint (pre-9/11), the bells go off and security find a rifle cartridge in the pocket of the older boy (purloined from the father's cartridge case).
The extent of the action taken by security was only the confiscation of the cartridge (although I suspect long laughter, well after the perpetrators had passed through).
I believe that the father's face (who shall remain nameless to protect the guilty) was red all during the flight....
