I believe that modern military cannot have a winning fight against guerilla warfare.
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You cannot destroy what you cannot find.
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Guerillas know the terrain and soldiers do not. The military intelligence might, but not the soldiers.
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Guerillas know enemy soldiers locations first buy mere observation.
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Guerilla fighters are a cornered animal. They have one way out, through the invader.
Edit: the only way that a modern military can fight it, is blanket indiscriminate destruction.