Title: Technologies of Decision Support and Proportionality in International Humanitarian Law
Abstract: Abstract What does proportionality reasoning mean for decision support in international humanitarian law ( ihl )? We first consider contemporary ihl commentaries on proportionality as an analogue form of decision support through a paradigmatic example. Over time, proportionality in ihl has changed from being a rule-specific space for discretionary decision making to a much broader compromise-seeking within boundaries marked by law. Today, proportionality is a master norm in ihl , remaking rules by stealth and enabling the accommodation of novel master technologies as lawful. Artificial Intelligence ( ai ) support for military decision making is one such master technology that resonates particularly well with the inner structure of proportionality thinking: both build on cost-benefit analysis and engender the quantification of the world through data collection. We analyse how cost-benefit analysis and digitalization and algorithmic processing intersect in the U.S. legal context, to then proliferate into U.S. warfare and decision support systems, and onwards into ihl .