This document discusses the evolution of U.S. foreign policy from the late 1700s to present day under various presidential administrations. It outlines the shift from isolationism to growing international involvement through manifest destiny and expanding global influence. Key doctrines and events discussed include the Monroe Doctrine, Wilsonianism, the Truman Doctrine, containment during the Cold War, and unilateralism under Bush giving way to renewed multilateralism under Obama through pragmatic realism. It also examines the role of the U.S. military industrial complex and global perceptions of American power and diplomacy over time.