What is a 'proportionate response'?

(JNS) — In the Western mind, proportionality in war is simply a numbers game. The side that inflicts more casualties is acting disproportionately, is in the wrong and may even be committing crimes against humanity. This has no basis in international law, but it is useful as a rhetorical weapon.

Israel’s enemies make prodigious use of this numbers game, which is no surprise. After all, when Israel is fighting a terrorist entity that uses civilians as human shields in order to increase body counts, which are then used to manipulate journalists and international leaders, it is fighting an uphill...