My argument is NOT that there were no hijackers.
I think all of us will be surprised that this gentleman didn't end up screaming "Don't taze me bro!" It just goes to show how exercising your rights, peacefully, if somewhat stubbornly, can still work even in the USA of 2008.
Immigration checkpoints reek of police state. Remember, once a person/vehicle has cleared the border, they should not have to be randomly stopped AGAIN. Jesse Ventura discussed these kinds of checkpoints in his book and on the Meria Heller interview. He said he'd refuse to even show his driver's license unless it's a state trooper, and reminds us that the Constitution forbids the random stopping of Americans within America without probable cause.