Jonah, that is a great question … and not an unprecedented one. Recall the antrax attacks right after 9/11. They sparked a number of copycat-type acts — people (including some teenagers) who thought it would be effective (or humorous) to put baby-powder and the like in envelopes as threats or pranks against the targeted victims. In the atmosphere of the time, these episodes not only frightened the recipients but cost the authorities involved lots of money — causing first responders to come out in force (and, of course, making them potentially unavailable, or at least late, in the event there had been a real emergency).
In trying to figure out what to do about these (it’s not instantly clear, by any means, that there is even federal jurisdiction over, let alone a federal crime involved in, these types of acts), I came upon a provision in the anti-terrorism legislation enacted in the mid 1990s, Section 2332a of Title 18. This makes it a felony not merely to use, conspire or attempt to use a weapon of mass destruction, but even to threaten to use a weapon of mass destruction.
The few faux-anthrax prosecutions that actually resulted were not very successful. When these things first happen, you want to wring the neck of the offender. But months later (cases usually get decided long after, when passions have cooled), the charge looked like overkill to a lot of people. It’s obviously intended to nab real terrorists: the potential penalty is “any term or years or for life, and if death results, [offenders] shall be punished by death or imprisoned for any term of years or for life.” Also, if the “attack” (including a threat) is directed at persons within the U.S., you have to show at least a potential effect on interstate commerce.
Nevertheless, with the flying imams, I sure think it would be worth seriously exploring this kind of prosecution. It was done with such deliberation by mature (chronologically, at least) persons in a way patently designed to instill in passengers and crew the fear of 9/11 — to be specific, the threat that the plane was about to be used as a weapon of mass destruction, gravely endangering them as well as thousands of other potential victims.
Of course, such a case could only be brought by a government not in mortal fear of being accused – during a war with Islamic terrorists, no less – of anything remotely resembling the profiling of Muslims … even Muslims who consciously ape Islamic radicals (and then — to complete the perfect circle — presume to complain about being profiled!). Thus, I am not holding my breath. Such an indictment would no doubt mean sensitivity training for the entire Justice Department, to say nothing of the grand jury.