"Terrorism" is certainly a well-defined crime in the US. See e.g. here, in particular:
(5) the term “domestic terrorism” means activities that ... (B) appear to be intended ... (ii) to influence the policy of a government by intimidation or coercion
(note the word appear to be intended)
The realistic worst-case scenario depends on how pissy the prosecutors are feeling and whether they need a sacrificial goat at this particular moment. See today's Popehat for a sense of how wide the prosecutorial discretion is.
You're skipping the first test ("violent acts or acts dangerous to human life"), which is why this doesn't qualify. No violence, no danger: not terrorism by federal standards.
Think about this from the prosecutor's perspective. You're looking at an obvious publicity stunt. Normally this sort of thing would be prosecuted under state law, which is what I was trying to get at with "most jurisdictions", but let's say you're working under the US Code for... reasons. Maybe our perp crossed state lines. Now, you don't want to encourage thi...
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
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