United States war plans for a conflict with the Soviet Union (USSR) were formulated and revised on a regular basis between 1945 and 1950. Although most were discarded as impractical, they nonetheless would have served as the basis for action had a conflict occurred. At no point was it considered likely that the Soviet Union or United States would resort to war, only that one could potentially occur as a result of a miscalculation. Planning was conducted by agencies of the Joint Chiefs of Staff, in collaboration with planners from the United Kingdom and Canada.
American intelligence assessments of the Soviet Union's capabilities were that it could mobilize as many as 245 divisions, of which 120 could be deployed in Western Europe, 85 in the Balkans and Middle East, and 40 in the Far East. All war plans assumed that the conflict would open with a massive Soviet offensive. The defense of Western Europe was regarded as impractical, and the Pincher, Broiler and Halfmoon plans called for a withdrawal to the Pyrenees, while a strategic air offensive was mounted from bases in the United Kingdom, Okinawa, and the Cairo-Suez or Karachi areas, with ground operations launched from the Middle East aimed at southern Russia. By 1949, priorities had shifted, and the Offtackle plan called for an attempt to hold Soviet forces on the Rhine, followed, if necessary, by a retreat to the Pyrenees, or mounting an Operation Overlord–style invasion of Soviet-occupied Western Europe from North Africa or the United Kingdom.
Despite doubts about its viability and effectiveness, a strategic air offensive was regarded as the only means of striking back in the short term. The air campaign plan, which steadily grew in size, called for the delivery of up to 292 atomic bombs and of conventional bombs. It was estimated that 85 percent of the industrial targets would be completely destroyed. These included electric power, shipbuilding, petroleum production and refining, and other essential war fighting industries. About 6.7 million casualties were anticipated, of whom 2.7 million would be killed. There was conflict between the United States Air Force and the United States Navy over naval participation in the strategic bombing effort, and whether it was a worthwhile use of resources. The concept of nuclear deterrence did not figure in the plans.
Background In 1944, at the height of World War II, the Joint Chiefs of Staff (JCS) forecast that the war would result in the United States and the Soviet Union becoming the leading world powers. While Britain was still an important power, its position was greatly diminished. On 5 February, the JCS produced an assessment of Soviet post-war intentions. It was expected that the Soviet Union would demobilize most of its forces to facilitate the reconstruction of its economy, which had been devastated by the war, and was not expected to recover before 1952. Until then, the Soviet Union would seek to avoid conflict, but for its own security it would attempt to control border states. Even after demobilization, the capabilities of the Soviet Union would be formidable. American intelligence reports estimated that it would retain over 4,000,000 troops under arms, with 113 divisions. Another 84 divisions would be available from satellite nations.
During World War II, the United States mobilized the largest armed forces in American history. The United States Army, which at the time included the United States Army Air Forces (USAAF), had a strength of 8.3 million, of which 3 million were deployed in the European Theater of Operations, and the United States Navy and United States Marine Corps had a combined strength of 3.8 million. By early 1945, plans called for 21 divisions (about 1,000,000 personnel) to be redeployed from Europe to the Pacific via the United States for the invasion of Japan. About 400,000 personnel were to remain in Europe on military occupation duties, and the Army would release 2 million personnel from active duty under a points system whereby soldiers were awarded points based for length of service, length of overseas service, children and decorations. Those with the highest scores had priority for separation from the Army. By the time of the surrender of Japan in August 1945, 581,000 Army personnel had been separated. Under overwhelming public and political pressure, the demobilization of United States armed forces after World War II proceeded much faster than originally planned. By 30 June 1946, the strength of the Army had declined to 1,434,000, the Navy to 983,000 and the Marine Corps to 155,000; by 30 June 1947, the Army was down to 990,000, the Navy to 477,000 and the Marine Corps to 82,000, and only one division remained in Europe. Meanwhile, the economies of European nations were still recovering from the war, and their ability to maintain forces was constrained.
The Joint Staff Planners (JSP) consulted with Vannevar Bush, the Chairman of the Joint Committee on New Weapons and Equipment, and Major General Leslie R. Groves, the director of the Manhattan Project, on the potential of new weapons then under development, in particular nuclear weapons and long-range missiles. Bush doubted that it was possible to build a missile like the German V-2 rocket of World War II, but with an extended range of . Even if the rocket was possible, it would still require allied overseas bases to reach the Soviet Union. Groves was more optimistic; while he agreed that long-range missiles were not technologically feasible in 1945, he thought that they might be in the next ten to twenty years. As for atomic bombs, he recommended that a stockpile be built up but warned that the destruction of a nation's industrial capacity would not affect the outcome of a war.
The JCS fashioned a defense posture and war plans oriented toward a single contingency—an all-out global conflict. Mainly they relied on strategic bombardment with nuclear weapons as the country’s principal deterrent and first line of defense. This strategy was found as most practical, effective, and affordable form of defense, and laid foundation for a series of war plans developed over the next few years for dealing with a possible conflict with the Soviet Union.
Pincher (1946) On 2 March 1946, the Joint War Plans Committee (JWPC) circulated a discussion paper for an outline war plan codenamed Pincher. The outline, which was revised in April and June, estimated that the Soviets could deploy 270 divisions in Europe, 42 in the Middle East, and 49 in the Far East sixty days after mobilization. The most likely flashpoint for hostilities was the Middle East, where Soviet ambitions might come into conflict with those of Britain. The United States would be neutral in such a conflict, but might eventually be drawn into it, as had occurred in 1917 and 1941. The Soviet Union had the resources to quickly overrun Europe east of the Rhine. The Rhine was a major barrier, but it was anticipated that it could not be held for long, forcing US and British forces to retreat to the Pyrenees. The planners believed that the Italian, Iberian, Danish and Scandinavian peninsulas could be held against superior numbers, but expected that the British and French forces would concentrate on defending their homelands, and would be unwilling to divert the resources required to hold Scandinavia, although they might assist in attempting to hold Spain and Italy. The Soviet drive into Western Europe would likely be accompanied by one into the Middle East. If the Soviets also attacked in the Far East, US forces would fall back to Japan.
The objective of the United States forces would be to hold the British Isles, North Africa, India, China and Japan, from whence strategic air operations could be launched, while the Navy blockaded the Soviet Union's ports. The concept of launching a second Operation Overlord was rejected; it would involve fighting the Soviet forces where they were strongest, and far from their homeland. The possibility of recapturing Scandinavia was considered, but the logistical difficulties were great. The preferred course of action was therefore to attack the Dardanelles and Bosporus, and invade the Soviet Union via the Black Sea. The plan did not specifically call for the use of nuclear weapons, although it noted that bases within Boeing B-29 Superfortress range of key targets were lacking. At the time the B-29 was the USAAF's most advanced long-range bomber. There was no concept for operations beyond the initial counter-offensive, and the logistical implications of deploying a large force in the Middle East were not explored. Nonetheless, on 8 July 1946 the Joint Strategic Planners accepted Pincher as the basis for planning.
The JWPC and the Joint Intelligence Committee (JIC) then produced a series of regional studies based upon Pincher. The first was Broadview, which was issued on 5 August, and revised on 24 October 1946. It dealt with the defense of North America. Long-range weapons meant that the heartland could no longer be considered invulnerable. In the immediate future, the Soviet Union was capable of conducting one-way air strikes and commando raids, and submarines could attack shipping and lay mines in American waters. The major threat, though, was seen as sabotage and subversion by Soviet agents. After 1950, there was a possibility the Soviet Union would develop nuclear weapons, and the long range aircraft or missiles to deliver them against cities in the United States. The possibility of an invasion of Alaska was also considered. To counter these threats, the United States would need mobile ground forces to counter raids, an air warning system, and antisubmarine forces.
Plan Griddle, which was issued on 15 August 1946, dealt with the defense of Turkey. The Turkish Army was large, with 48 divisions, but it lacked modern equipment. The study estimated that the Soviet Union could deploy up to 110 divisions against Turkey without compromising operations elsewhere. A two-pronged advance was envisaged, with an attack on Eastern Thrace from Soviet-aligned Bulgaria, coupled with one into Anatolia from Soviet Transcaucasia. Airborne and amphibious forces could strike at both sides of the Dardanelles and Bosporus. From Turkey, Soviet forces could advance into Iraq and Iran. It was estimated that Turkey could hold out for at most 120 days before Turkish forces had to fall back to the western Anatolian coast. Nonetheless, Turkey figured large in American strategy as a potential base for air attacks on the Soviet Union, and blunting the Soviet drive into the Middle East. The study therefore called for increased military aid to Turkey, and development of Turkish airbases and ports.
This led to the next study, which was issued on 2 November 1946. It was codenamed Caldron, and dealt with the Middle East. While the Soviet Union produced ample oil for its own peacetime needs, the planners felt that it had insufficient reserves for a major conflict, and therefore that seizing the oil resources of the Middle East would be a Soviet priority. Conversely, this would deny them to the Allies. The region was also considered as an important staging area for an attack on the Soviet Union, so it was expected that the Soviets would move to preclude that. Up to 85 Soviet divisions would be available for operations in the Middle East, where the British would have five divisions to stop them. Soviet forces were expected to reach Palestine within 60 days. About 14 Allied divisions could be concentrated in Egypt.