This article examines three arguments according to which the Iraq war has been justified: preemptive or preventive self-defense, law enforcement, and humanitarian rescue. It concludes that for empirical and moral reasons, the Iraq war lacks a just cause. In the course of making that judgment, the article explores moral and practical implications of a preventive war policy. It also examines efforts to invoke one justification—rescue—retrospectively to justify the war. The article claims that such ex post justifications confuse the meaning of intention and, wittingly or unwittingly, allow leaders to authorize a resort to force in bad faith. Retrospective justifications also fail to understand that different burdens are attached to ad bellum rationales. That claim is premised on the idea that self-defensive wars join duty and interest in ways that wars of rescue do not. To assume that arguments can shift from self-defense to rescue, without recognizing that these entail different kinds of sacrifice, is to discount the respect due to those whose sacrifice is required. If altruistic policies are expected to be carried out by soldiers, stronger reasons than self-defensive purposes are necessary to justify the risks, reasons that avoid the allegation of leading in bad faith.