The purpose of this article is to examine the difficult issues of "characterization" that an armed conflict like Operation Just Cause presents and, based upon that characterization, to determine which sets of humanitarian law norms apply to the conflict. The first section of the article discusses certain aspects of the conduct of hostilities that have received some degree of media attention. That section addresses issues associated with international law obligations to warn the civilian population of impending attack, and the rules of military necessity and proportionality as applied to certain targeting issues affecting civilians. The second section of the article addresses the treatment of Panamanian civilians as "protected persons" by United States forces. The third section focuses on the inviolability of diplomatic premises in wartime. The article concludes that the United States forces met their humanitarian law obligations in Operation Just Cause, conceding ever-present shortcomings in some particulars and unfortunate unplanned incidences of personal misconduct.