Proportionality and Necessity in Israel’s Invasion of Gaza: A Reply to McMahan

Jeff McMahan has recently argued that Israel’s current military campaign in Gaza constitutes an unjust war on the grounds that it fails to satisfy the requirements of proportionality and necessity. His case rests on a comparative moral calculus: the harm inflicted on Palestinian civilians is judged excessive in relation to the number of Israeli lives saved, even when granting special weight to the lives of one’s compatriots. However, his account is marked by several analytical limitations. His treatment of associative duties is reductive, grounding their moral force exclusively in co-nationality and neglecting thicker accounts of collective responsibility. He also adopts a narrow conception of benefit, focused entirely on immediate lives saved, while bracketing other morally salient goods such as long-term security or deterrence. His account of civilian liability is similarly narrow in scope, relying on prior electoral support while disregarding broader forms of collective entanglement. Finally, his critique of necessity relies on counterfactuals and general trends – such as civilian harm and cycles of retaliation – that, if applied universally, would challenge the justice of nearly all wars. These limitations significantly compromise McMahan’s analysis and render his conclusion – that Israel’s military campaign fails the just war criteria of proportionality and necessity – unpersuasive.