From the FBI website:
Terrorism Definitions
International terrorism: Violent, criminal acts committed by individuals and/or groups who are inspired by, or associated with, designated foreign terrorist organizations or nations (state-sponsored).
Domestic terrorism: Violent, criminal acts committed by individuals and/or groups to further ideological goals stemming from domestic influences, such as those of a political, religious, social, racial, or environmental nature.
With the above in mind, it seems to my untutored mind that the American Airlines mechanic, who is the subject of this thread, attempted an act of terrorism.
Christmas Cheers,
Grog