U.S. Role in the World: Background and Issues for Congress [Updated August 26, 2020] [open pdf - 1MB]
From the Introduction: "This report provides background information and issues for Congress regarding the U.S. role in the world, meaning 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. [...] The issue for Congress is whether the U.S. role in the world has changed, and if so, what implications this might have for the United States and the world. Congress's decisions regarding the U.S. role in the world could have significant implications for numerous policies, plans, programs, and budgets, and for the role of Congress relative to that of the executive branch in U.S. foreign policymaking."
CRS Report for Congress, R44891
Congressional Research Service: https://crsreports.congress.gov/