U.S. Role in the World: Background and Issues for Congress [Updated March 31, 2020] [open pdf - 1MB]
From the Summary: "The U.S. role in the world refers to the overall character, purpose, or direction of U.S. participation in international affairs and the country's overall relationship to the rest of the world. The U.S. role in the world can be viewed as establishing the overall context or framework for U.S. policymakers for developing, implementing, and measuring the success of U.S. policies and actions on specific international issues, and for foreign countries or other observers for interpreting and understanding U.S. actions on the world stage. While descriptions of the U.S. role in the world since the end of World War II vary in their specifics, it can be described in general terms as consisting of four key elements: global leadership; defense and promotion of the liberal international order; defense and promotion of freedom, democracy, and human rights; and prevention of the emergence of regional hegemons in Eurasia."
CRS Report for Congress, R44891
Congressional Research Service: https://crsreports.congress.gov/