As the United States faces new foreign threats and security challenges, U.S. foreign-policy makers continue to find novel ways of using military force abroad. During the Obama presidency, the United States has engaged in a number of controversial military operations that remain politically contentious and unresolved today. The political process between the president and the Congress over when and how to use the military remains as relevant as ever. In this study of the use of U.S. military power abroad, Ryan C. Hendrickson examines the political process between the president and Congress that has led to military action during the Obama presidency. In his case study analyses of military action in Afghanistan and the corresponding drone missile strikes, counterpiracy operations on the Indian Ocean, the U.S Special Forces hunt for African warlord Joseph Kony, and the U.S. air strikes on Libyan leader Muammar Qaddafi, Hendrickson finds that President Barack Obama has acted much like previous commanders in chief, who often made unilateral military decisions for the United States. Presidents draw their own “red lines” for war with little input from Congress. In contrast to other research on Congress’s role in shaping U.S. foreign policy, Hendrickson also finds that congressional deference remains the norm on war powers issues. An absence of partisanship in Congress on this issue, perpetuated by Congress’s senior leadership from both parties, helps explain why the commander in chief is given such wide latitude in foreign and military affairs.