DEFINING TERRORISM

"Terrorism" is a word used so often and so loosely that it has lost a clear meaning. The term terrorism is sometimes merely applied because someone disagrees with the cause. Hence the expression "One man's terrorist is another man's freedom fighter." World peace not only requires an end to war, but terrorism as well.

Expected result of the violence: Let's define an action as "terrorism" if the use of violence would reasonably be expected to harm innocent civilians. This is to be distinguished from a "military" action, where the use of violence is not reasonably expected to harm innocent civilians.
Nature of the actor: A "state" action would be one conducted by a sovereign government. A "guerrilla" action will be one conducted by a non-governmental entity.
Four different types of violent acts: Hence, we can have both state military actions and state terrorism actions. Likewise, there can be both guerrilla military actions and guerrilla terrorism actions.

Under these definitional guidelines, if a country sends its bombers to destroy the water system or other civilian infrastructure of another nation, this would be a state act of terrorism, because harm to civilians would reasonably be expected to result. On the other hand, if a country sends its bombers to attack military airfields of its enemy, that would be a state military action.
Similarly: if a group fighting to overthrow a government or end an occupation by a foreign power sends a suicide bomber to blow up a civilian pizzeria, this would be a guerrilla act of terrorism. In contrast, if such a group sends a small boat filled with explosives to blow up a military vessel, that would be a guerrilla military action.

While these definitional results may stick in the craw of some, the value is that the killing of innocents will be condemned equally no matter who does it, and for however allegedly wonderful the ends sought.