Israel’s War Against Gazans: A Response to Lucas

This article defends the claims of an earlier article (“Proportionality and Necessity in Israel’s Invasion of Gaza, 2023–2024”) against objections advanced by Simon Lucas in “Proportionality and Necessity in Israel’s Invasion of Gaza: A Reply to McMahan.” It defends earlier arguments and develops new arguments to show that Israel’s war in Gaza between October 7, 2023, and late October 2025 has egregiously violated two moral principles that govern both the resort to war and continuation of war. These principles require that war be proportionate and necessary. Among the claims defended here are that Lucas’s collectivist conception of war and his appeals to principles of reciprocity are deeply implausible.