 The common judgment that strategic bombing is permissible provided that it is proportionate also deserves more scrutiny than it usually receives when it is taken to be justified by the principle of double effect. How much of an obligation do military strategists have to avoid harm to civilian populations? This is a substantive issue about the conventions that constrain military decision-making and the principles that underlie these conventions. Many relevant considerations depend on judgments that are far outside the ambit of Double Effect. For example, the Rules of Customary International Humanitarian Law displayed on the website of the International Committee of the Red Cross prohibit attacks targeting civilians. They also include protections denied to minimize harm to civilians: 