I can only see guerrilla warfare being clever and useful. The practice of guerrilla warfare in itself is not unjust. Having the advantage of knowing a particular terrain, hiding on higher ground above your adversaries, and then sneaking around while concealed to later attack is not a dirty tactic. It’s using the resources and ingenuity at one’s disposal that happen to simply be there.
It’s no different than regular war. If a war is a just war, then you may use guerrilla tactics. If a war is not a just war, then you shouldn’t be fighting it at all, either with guerrilla tactics, or more regular tactics.
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