How quickly the tables can turn.

Check out this surveillance camera from a liquor store in Marionville, Missouri catching an armed robber getting a taste of his own medicine when the cashier whips out a gun of his own.

As it turns out, the cashier is Jon Alexander, 54, who just so happens to have done four tours of duty in Iraq during a 30-year military career.

So, now it's official: some yahoo trying to take a couple of bucks from the till is clearly not as scary as trolling around Baghdad.

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