註釋 This important report analyzes the impact of nuclear weapon on the doctrine and force structure of the U.S. Army during the Early Cold War (1947-1957). It compares these impacts with those that occurred on the U.S. Air Force and Navy during that time. Nuclear weapons brought a new aspect to warfare. Their unprecedented economy of destructive power changed the way nations viewed warfare. For the Army, nuclear weapons presented a dual challenge. The Army faced a U.S. security policy centered on the massive use of these weapons; the Army also struggled to understand how these weapons would be utilized on the battlefield. The nation's security policy of large scale strategic nuclear bombardment of the Soviet Union favored the Air Force and to a lesser degree the Navy. The Army viewed this policy as single minded and purposely limiting the nations options to all out nuclear war or deference to another national will. In all the Army faced an internal struggle to incorporate these weapons and an external struggle to retain a useful position within the U.S. Defense establishment during this period.This compilation includes a reproduction of the 2019 Worldwide Threat Assessment of the U.S. Intelligence Community.I. The Army Before Last: Military Transformation and the Impact of Nuclear Weapons on the U.S. Army in the Early Cold War * A. Introduction * B. Current Military Transformation * C. The Nuclear Revolution * D. The Military Services And Nuclear Weapons * E. Thesis and Design * II. The Nuclear Revolution and The United States Air Force and Navy * A. Introduction * B. Revolutions * C. Defining the New Threat 1947-1955 * D. Policy to War Plan * E. Decisive Air Power * F. The Strategic Air Command * G. Early Cold War Naval Power * H. Bomber and Supercarrier * I. Conclusion * III. The Army's Atomic Force Structure * A. Introduction * B. The Korean Conflict * C. Army Nuclear Forces * D. Conflicts * E. Conclusion * IV. The Army's Atomic Age Doctrine * A. Introduction * B. Soviet Early Cold War Strategy * C. Countering The Threat * D. Atomic Doctrine And Units * E. Conclusion * V. Conclusion * A. Introduction * B. The Comparisons - Then and Now * C. The Impacts * D. ConclusionThe current U.S. military is essentially the product of the combat lessons of World War II and the preparations to fight the Soviet military during the Cold War. Tactics, techniques and equipment refined during both of those wars led to the victory in Desert Storm as well as the success of the peacemaking and peacekeeping operations in Bosnia and Kosovo. Ongoing efforts throughout the 1990's to capitalize on emerging information technologies enhanced the forces that defeated the Taliban in Afghanistan in 2001 and ousted Saddam Hussein in Operation Iraqi Freedom two years later. The Army is always changing, by improving its weapons systems, altering its force structure, or refining its doctrine and tactics. This process always involves the interaction of recent combat experience, budget realities, and the exploitation of a new technology. Any change in an institution such as the Army is a skilled balance of risk versus reward. The early Cold War represented a comparably intense period for military change. Before the Second World War, the American army and navy had been primarily hemispheric defense forces. The challenge of defeating both Germany and Japan required a massive land force for Europe and an equally large naval force for the vast Pacific theater. Furthermore, World War II saw an exceptional growth of military technology including improved mechanization, radios, jet engines, and, most significantly, the atomic bomb. 