The Critical Threats Project and Institute for the Study of War teams began to examine various options against ISIS and al Qaeda in Syria as local, regional, and global conflicts were escalating. The teams tested 15 different courses of action. The goal was to destroy both ISIS and al Qaeda without sacrificing wider American interests or accepting undue cost or risk. Most COAs failed because they strengthened jihadists, undermined US allies, empowered Russia and Iran at America’s expense, or prolonged and expanded the Syrian war in ways that endangered America’s vital interests. The most dangerous action, however, proved to be inaction.