provide and maintain a navy during peacetime and war. It also provided for the militia, which it put under state control, but it gave the Congress the power to call the militia for federal purposes. Thus, the foundation of our military organization was a small standing force backed by a larger militia force.

The early 20th century saw the beginnings of a federal reserve force entirely separate from the militia, which by then was known as the National Guard. The Army and Naval Reserve were placed under federal control and were not subject to call for state missions. Some 200,000 of the 4.7 million Americans who served in World War I were mobilized National Guardsmen or filler personnel from the new federal reserve components. A combination of regular and National Guard units provided 17 combat divisions; 2.8 million draftees supplied additional manning. After World War I, these standing forces were largely disbanded.

When the war in Europe commenced in 1939, the strength of the regular Army was at 190,000. The Army's organized reserve strength included 104,228 officers and 3,233 enlisted personnel who were available for wartime service. Between September 1940 and June 1941, eighteen Army National Guard divisions composed of 300,000 personnel were mobilized in increments. In addition, the Naval Reserve was mobilized in May 1940. By the time Pearl Harbor was attacked, there were 45,000 Naval Reservists on active duty. At the end of the war, American forces numbered over 12 million men and women in uniform, including conscripts and volunteers. A total of 16 million Americans had served. Once again, relatively small standing forces and reservists, reinforced by conscripts and volunteers, proved to be a workable structure that permitted adequate time for a large-scale mobilization and the equipping and training of combat units before employment. After the war, American forces were rapidly demobilized, and by 1948, the active force had declined to 1.4 million personnel. The strength of the reserve components was 2.6 million.

The invasion of South Korea in June 1950 presented unexpected manpower needs that did not fit with a strategy that called for full mobilization. The time for training, deployment, and employment was limited, and the United States suddenly faced a requirement for substantially larger forces than it had on active duty. After the rapid and massive demobilization following World War II, the country had come to rely more on volunteers and conscription to expand the active force than on the mobilization of reserve components. During the first year of the Korean conflict, over 2 million men and women entered active military service. Mobilized personnel were split evenly among the National Guard and Reserve, voluntary enlistments, and draftees. The need at the beginning of the conflict for trained individuals to fill units and provide replacements resulted in the mobilization of 168,000 individual reservists, including large numbers of World War II veterans who had not trained since their release from active duty following that war. With as little as three days' notice and twelve days of retraining they provided squad

leaders for the Korean Augmentation to the US Army, thereby demonstrating that certain soldier and survival skills can be regained quickly. Because of insufficient resources, however, the readiness of sume Army Reserve units had deteriorated rapidly after World War II, and those units required as much as a year of additional training before they could be deployed.

The Marine Corps experienced greater success in recalling reservists for the Korean conflict. Over 90 percent reported quickly to their units, and an additional 5 percent responded to the call-up with only minimal delays. Upon arriving at Camp Pendleton, California, after mobilization, all reserve ground units were disbanded and individual reservists were reassigned to active combat units to alleviate manning shortfalls. Most of the reserve aviation squadrons were employed as units rather than as individual replacements. By the end of the conflict, reservists made up 45 percent of the total Marine force of 192,000 and 48 percent of the Marine forces deployed to Korea. Between August and December 1950, more than 88,000 reservists either reported to Korea as replacements or filled training and support establishment billets in the continental United States (CONUS).

This first experience in the post-World War II era demonstrated the difficulty of using reserve forces for rapid mobilization when their readiness has been permitted to decline. Eventually, eight Army National Guard divisions (138,600 personnel) and many support units were mobilized, as were 14 separate battalions and 40 separate companies of the Army Reserve and 147,000 Air Force reserve component personnel. Only two of the Army National Guard divisions, however, were sent to the Pacific. Two others were sent to Germany in support of the newly formed North Atlantic Treaty Organization (NATO), and four remained in the United States as training divisions and a source of replacements. This raised the issue of how to determine who was to serve when not all forces were engaged. It was clear that a new organization of forces was needed for the new circumstances facing the United States as a global power. As a consequence, after the Korean conflict, active forces were retained at much higher readiness and force levels to compensate for reduced reserve readiness.

Since 1953, U.S. reserve forces have been called to active duty for international crises on several occasions, including the current call-up for Operation Desert Shield. There have also been several federal call-ups of the reserve components in connection with civil emergencies (see Table 11 During the Berlin crisis in 1961, the Congress authorized the President to mobilize 250,000 Ready Reserve personnel for 12 months. Approximately 155,000 reservists served on active duty during the crisis, including 39,000 members of the Individual Ready Reserve. During the Cuban missile crisis in October 1962, the President was given authority to call up as many as 150,000 Ready Reservists for 12 months. Over 14,000 Air Force reservists were ordered to active duty at that time. During both crises, the mobilization of reserve furces served as a means of demonstrating U.S. resolve.