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Air and Space Defense

Air and Space Defense. Recognizing that the two great oceans that had protected the United States from invasion for more than a century could now, at least in theory, be overcome through aerial assault, the administration of President Franklin D. Roosevelt after the outbreak of World War II in September 1939 began to rearm the nation. A sizable investment in this effort went to the Army Air Corps, which was woefully inadequate to meet the needs of national defense. In April 1939, when Congress passed the National Defense Act of 1940, it authorized the Army Air Corps to develop and procure 6,000 new airplanes, to increase personnel to 3,203 officers and 45,000 enlisted, and to spend $300 million, much of it directly earmarked for defense of U.S. territory. As a result, the aviation forces received $70.6 million, 15.7 percent of the army's direct appropriations. This number and the percentage continued to climb during the early 1940s.

After the attack on Pearl Harbor of 7 December 1941, the ability of the Japanese Navy to strike American forces on the West Coast could not be dismissed. On 9 December, Gen. “Hap” Arnold, commanding the U.S. Army Air Corps, directed that all aircraft on the West Coast be dispersed so that a single attack could not destroy significant military capability. He also placed air squadrons along the borders on alert, relocated most support infrastructure to the interior, and set into motion the modern approach to defense of the nation's perimeter.

During World War II, coastal aerial attacks on the United States were limited to a few Japanese balloons carrying bombs over the West Coast in 1944 and 1945. However, the effect of World War II on thinking about U.S. national defense proved crucial. Two major technological developments rendered the nation particularly vulnerable to outside attack: the long‐range strategic bomber (especially if carrying atomic bombs), and the ballistic missile, which had enormous potential for intercontinental attack (also with atomic warheads). During World War II, the strategic bombing campaigns in Europe and Asia represented for many the “creation of Armageddon”; estimates well in excess of 100,000 deaths took place in the two atomic bombings of Hiroshima and Nagasaki, Japan. Likewise, the German V‐2 rocket demonstrated the potential of missiles for long‐range attack. As the first true ballistic missile, the V‐2 flew at speeds of over 3,500 miles per hour and delivered a 2,200‐pound warhead 500 miles away. First flown in October 1942, it was employed against targets in Britain beginning in September 1944. By the end of the war, 1,155 had been fired against England and another 1,675 had been launched against Antwerp and other Continental targets. The guidance system for these missiles was imperfect and many did not reach their targets, but they struck without warning and there was no defense against them. As a result, the V‐2 had a terror factor far beyond its capabilities.

Following World War II, despite postwar demobilization, the Cold War precipitated a continuation of the expansion of military aerospace activities and fostered the search for a truly effective air and space defense for the United States. In the process, the air arm became an independent service, the U.S. Air Force, in 1947. The military air and space component during the Cold War involved a broad range of activities: training, equipping, and employment of aerospace power extended from aircraft to missiles to satellites to other systems, both passive and active. Much of this, such as satellite reconnaissance, was carried out in a highly classified environment, with neither details nor records of government available for ready inspection. All has been justified as a means of maintaining integrity against an aggressive threat from Russia and other global rivals.

In this context, U.S. air and space defense strategy developed in two distinct ways. First was the development of offensive strategic nuclear forces capable of deterring any attack on the United States—either by striking an enemy before it had a chance to inflict significant damage, or by being able to retaliate massively in response to a strike.

To execute this deterrent mission, the Department of Defense (DoD) created such organizations as the Strategic Air Command (SAC) in the late 1940s, and placed in command Gen. Curtis E. LeMay, as rough and irascible an officer as the air force had, but he got results. LeMay fully understood that the nation's first line of defense—indeed, in many respects its only line of defense—was the nuclear deterrent that SAC was charged with maintaining. The command, he knew, had to be prepared to carry out its nuclear mission at any time for the deterrent to have viability. He therefore refined the procedures for strategic bombardment, both with intercontinental ballistic missiles (ICBMs) and strategic bombers, and he made them increasingly more effective. The preparedness of SAC to execute its mission became legendary and set standards of excellence still sought after within the air force, as SAC maintained a state of extreme readiness from the late 1940s through the early 1980s.

More broadly, this strategy ensured the development of what was know as the nuclear triad: U.S. continental‐based, long‐range strategic bombers; U.S. continental‐based intercontinental ballistic missiles (ICBMs); and sea‐launched intercontinental ballistic missiles (SLBMs) carried on submarines and therefore mobile. All of these could strike the Soviet Union—or anywhere else on the globe—with nuclear weapons and therefore ensure an enemy's destruction despite a United States in ruins. Sometimes referred to as mutual assured destruction, this doctrine was known by the most appropriate acronym ever coined by the military: MAD.

Second, perhaps more critical to air and space defense, was the development of early warning and interception systems by the United States. The first successful one was the DEW (distant early warning) Line, approved by President Harry S. Truman in 1952, across Alaska, Canada, and Greenland. Its purpose was to provide radar and other electronic surveillance of the Soviet Union to monitor technological progress and, more important, any possible hostile actions against the United States and its allies. The capability of this string of listening posts across the arctic was to be 100 percent detection for all weapons up to 100,000 feet in altitude, which would therefore handle ballistic missiles and bombers. A joint project, the United States provided the funding and supervision of the construction. The Canadians, with a similar system already in place in certain parts of their nation, would link with the DEW Line for an unbroken surveillance sequence in the arctic. This system was constructed quickly in the next two years, coming on line in 1957, and served its purpose throughout the Cold War. It was still operational, although its capabilities had been upgraded, at the close of the century.

To manage the DEW Line, and to respond to any threat detected, the United States and Canada created the North American Air Defense Command (NORAD) in 1957 (“Aerospace” was substituted for “Air” in the title in 1981). Based at Cheyenne Mountain a few miles outside Colorado Springs, for more than three decades NORAD provided integrated command of air and space defense forces of the two nations. It directed dedicated interceptors, other fighters, surface‐to‐air missiles, air and space detection and control centers, and other facilities to defend the continent against attack.

A U.S. service‐backed antiballistic missile (ABM) program was accelerated in 1967. But by the early 1970s, Russian work on an ABM system of ultra‐high‐speed missiles and phased array radars threatened to destabilize deterrence. In 1972, one of President Richard M. Nixon's arms control agreements was an ABM treaty limiting deployment to two ABM sites.

Another major component in the U.S. air and space defense system was the strategic reconnaissance efforts of space satellites. Under development in the late 1950s, Project CORONA was the first successful reconnaissance satellite program. Essentially, the objective was to obtain high‐quality satellite photographs of the Soviet Union and thereby ensure that the United States would never suffer another Pearl Harbor–like surprise attack. As part of this effort, the first satellite, launched 18 August 1960, reached orbit and then correctly returned its reentry vehicle containing photographs of the Soviet ICBM base at Plesetsk and the bomber base at Mys Schmidta. The satellite was plucked from the Pacific Ocean by U.S. Navy frogmen. After this flight, CORONA became an operational mission and functioned through 1973, when it was succeeded by later generation reconnaissance satellite projects.

But strategic deterrence, satellite reconnaissance, and NORAD's warning and response capability were insufficient to guarantee safety against a determined enemy, and this prompted national security officials to seek an ultimate shield. The result was the Strategic Defense Initiative (SDI), unveiled by President Ronald Reagan in March 1983. An expansive, technologically complex, and exceptionally expensive research and development (R&D) program, SDI's aim was to create an array of space‐based technologies that could track and destroy incoming missiles. The project immediately became controversial because of its technical complexity, its high price tag, and because it would upset the strategic nuclear balance of power between the United States and the USSR that had succeeded in avoiding superpower war. With the collapse of the Soviet Union in 1989 and the end of the Cold War, SDI declined in importance and survived only as a modest R&D effort within the DoD in the mid‐1990s.

Indeed, with the end of the Cold War in the early 1990s, the U.S. air and space defense system underwent substantial changes. NORAD continues to exist, but as a component of U.S. Space Command and its mandate has been narrowed since there is no major strategic threat. Some of its response component has been transferred from the active military force to the Air National Guard. Some nuclear forces of the DoD have been taken off alert, some nuclear weapons destroyed, and SAC inactivated, and targeting of Russia has been deemphasized. The DoD component managing SDI has been reduced in size and funding and renamed the Ballistic Missile Defense Organization. Finally, public conceptions of air and space defense, such as civil defense in its various capacities, have been minimized.
[See also Arms Control and Disarmament; Canada, U.S. Military Involvement in; Deterrence; Missiles; Satellites, Reconnaissance.]


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Roger D. Launius

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