- Rising in revolt against established authority, especially a government.
- Rebelling against the leadership of a political party.
Using the same logic that labels Iraqis as insurgents, if Canada invaded America for harbouring some of the worlds most devestating and prolific international terrorists - however legitimate this charge may be - any American resisting the invasion could also legitimately be described as an insurgent. Somehow, I don't think Americans would see it quite like that.
Update: Someone even complained to the BBC about the inappropriate use of the word 'insurgent'.