The document discusses the key factors that influence the formulation of US foreign policy: 1) Institutions such as the executive branch, Congress, and various government agencies and bureaucracies play a role in both creating and implementing foreign policy. This process can involve struggles between the branches. 2) Ideas like moralism, realism, and neo-realism shape how policymakers view America's role in the world and its national interests. 3) Domestic and foreign interests, including defense contractors, also exert influence through lobbying and advocacy. Of these factors, institutions have the greatest formal role in actually creating foreign policy.