Stealth Change: How the United States and the United Kingdom Embraced International Humanitarian Limits on Nuclear Use

This article analyzes how American and British policy shifted, from rejecting to accepting the applicability of the law of armed conflict (LOAC) to nuclear use. Through a study of primary and secondary sources as well as interviews with protagonists, I argue that processes of international social pressure, domestic pressure, and domestic legal interpretation help explain this change. I show how, from 1965 onward, multilateral processes quietly began to promote international legal change in civilian protection in general, nuclear warfare included. Because early resolutions referred to general “principles,” not binding rules, British and American officials treated such language as lip-service. Gradually, official views transformed as government lawyers clarified their understanding of distinction, proportionality, and precaution as international customary LOAC principles applicable to all forms of warfare, including nuclear weapons.