Have you tried the airport security metaphor?
It goes something like this: "Take modern airport security. Then add a law saying that if, in addition to any current reasons for someone to be pulled aside and searched, they would also be pulled aside and searched if they said a 'danger word', if they were within five miles of the airport. And whenever someone is pulled aside to be searched, the entire airport is shut down. Indefinitely."
Edit:
You might also want to take a look at the single remaining Wikipedia article and its references for ideas on how to get the idea across to them.
Edit 2:
xkcd has some good links too.
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Stand between the Silver Crystal and the Golden Sea.
"Youngsters these days just have no appreciation for the magnificence of the legendary cucumber." --Krityan Elder, Tales of Vesperia.
It goes something like this: "Take modern airport security. Then add a law saying that if, in addition to any current reasons for someone to be pulled aside and searched, they would also be pulled aside and searched if they said a 'danger word', if they were within five miles of the airport. And whenever someone is pulled aside to be searched, the entire airport is shut down. Indefinitely."
Edit:
You might also want to take a look at the single remaining Wikipedia article and its references for ideas on how to get the idea across to them.
Edit 2:
xkcd has some good links too.
-----
Stand between the Silver Crystal and the Golden Sea.
"Youngsters these days just have no appreciation for the magnificence of the legendary cucumber." --Krityan Elder, Tales of Vesperia.