A selfish man who had others die for him
That's kind of a trite and glib statement, and one we've heard a lot. When I was in the military I heard people say quite often "If Osama thinks strapping a bomb to your chest to kill infidels is such a good idea, why doesn't he do it?" The answer to that is simply, the same reason George W. Bush didn't grab an M-16 and head to Fallujah.
The calculated use of unlawful violence or threat of unlawful violence to inculcate fear; intended to coerce or to intimidate governments or societies in the pursuit of goals that are generally political, religious, or ideological.
Based on the above definition the entire Revolutionary War is a textbook example of terrorism. The violence being used was definitely seen as unlawful by the crown, and the goal was to coerce England to relinquish control of the colonies. You could make arguments that the intent in the Revolutionary War wasn't to 'inculcate fear' but the same argument could be made of 9/11, all targets attacked caused significant military and economic damage.
My larger point is that terrorism is a BS term that isn't particularly useful in honest discourse. No government ever considers violence against it to be lawful, almost any large scale act of violence have goals that are political, religious, or ideological, and any party engaging in violence is generally hopeful that the threat of such will bring about it's goal without the actual exercise of violence.
No man is an island if he's on at least one mailing list.