Threatening... Often misconstrued as the actual act. However since 9/11... Threats are often treated nearly as harshly as the act.
We now understand yelling "FIRE!" in a crowded movie theater often ends in multiple deaths, and many injured. Joking about a bomb on an airplane will get you dragged off to security, and a body-cavity probe before you can say... "Kidding, just kidding!" And you may never fly again!
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Hmm. That address doesnt look right. It looks like the link pointing here was faulty.