Steve Fetter & Charles Glaser (2022) Legal, but Lethal: The Law of Armed Conflict and US Nuclear Strategy, The Washington Quarterly, 45:1, 25-37,
Starting around a decade or so ago, the law of armed conflict (LOAC) acquired new prominence in the development of US nuclear strategy. This was stimulated in part by a series of major intergovernmental conferences on the humanitarian impact of nuclear weapons, which led to a consensus among a group of nations that the use of nuclear weapons would result in catastrophic and unacceptable human suffering and was therefore incompatible with the LOAC.1 This argument has been a key rationale for efforts to prohibit nuclear weapons, including the 2017 Treaty on the Prohibition of Nuclear Weapons (TPNW), which as of early 2022 had 86 signatories and 59 states parties.
The United States has stated that it does not target “civilian population[s] per se” but this had not translated into dedicated efforts to avoid targeting civilians.2 In response to growing international support for the TPNW and other efforts to stigmatize and delegitimize nuclear weapons, combined with the United States’ desire to comply with international law, the United States began to require that its plans for the use of nuclear weapons are fully compliant with the LOAC. The LOAC requires that plans and decisions for the use of military force are guided by the principles of necessity, distinction, proportionality, and precaution.3 At the risk of some oversimplification, the LOAC prohibits attacks against innocent civilians and civilian targets, while permitting certain counterforce attacks (attacks against nuclear forces and command and control, and possibly conventional forces).