And? Show em your papers,keep em calm, and carry on. Right,wrong, or PITA though it may be, you are in a hostile environment-adapt until it gets set right.
Dont be a moron like the one in the story,and agitate the cop-esp. if he's already a candyasss,agitated and pointing his gun at you.That is NOT the time to be trying to "educate" the cop.
Do it after the fact, and take it up with his superiors, or in court, if need be.
Common sense: both rare commodities.