Adaptation under Fire looks at the essential importance of military adaptation in winning wars. Every military must prepare for future wars despite inevitably having little confidence about the precise shape that those wars will take. As former US secretary of defense Robert Gates once noted, the United States has a perfect record in predicting the next war: “We have never once gotten it right.” Despite this uncertainty, military organizations still must make choices. They must determine the nature of doctrine they will need to fight effectively, the type of weaponry and equipment they must procure to defeat their potential foe, and the kind of leaders they must select and develop to guide the force to victory. Since the US military has global security responsibilities, it will have to make these choices without knowing when, where, or how the next war will unfold, or even who the enemy may be. It will need to adapt quickly and successfully in the face of the unexpected in order to prevail. The book starts by providing a framework for understanding adaptation and includes several historical examples of success and failure. The second part examines US military adaptation during the recent wars in Iraq and Afghanistan and explains why certain forms of adaptation have proven so problematic. The final part argues that the US military must become more adaptable in order to successfully address the fast-changing security challenges of the 21st century, and concludes with some recommendations on how it should do so.