Since the Cold War the United States has fought three major wars. Congress authorized each of these wars. The president has also initiated several limited wars. These limited wars have not been explicitly approved by Congress as required by Article I of the Constitution. A review of the history of making limited wars suggests several conclusions. First, the president has assumed a de facto power to begin and pursue a limited war, understood as a struggle where no American combat deaths are expected. Second, Congress has at times been highly critical of such wars but also highly deferential to the president in cases where the wars were brief and popular. Third, an active and critical Congress can shape the president’s choices and decisions about such wars. Fourth, the public is often skeptical about limited wars and strongly supports congressional approval of such undertakings. Finally, until recently, presumed presidential authority under the Constitution was more important than the approval of international institutions in legitimating limited wars. In Libya the approval of the United Nations Security Council and other international institutions was essential to legitimating the war according the Obama administration. This incremental transfer of the war powers to international institutions contravenes the republican nature of the United States Constitution.