Photo Caption: Two members of the 1st Radio Broadcasting and Leaflet Group prepare loosely wrapped bundles of psywar leaflets for drops over North Korea.

In the Korean conflict, U.S. psychological warfare was a military affair, and no definitive assessment of its effect on soldiers and civilians in North Korea can be made. But a count of prisoners of war (POWs) taken by the United Nations forces revealed that about one-third claimed to have at least surrendered in part because of psychological warfare leaflets. Nearly every prisoner voluntarily taken had one or more U.N. leaflets. Psychological warfare was credited with a “nudging” effect on one’s willingness to surrender, though insufficient alone to cause surrender. The Chinese enlisted men were found the most amenable to the surrender mission of psywar, and the hard-core North Korean officer corps the least inclined.

The primary purpose of psywar was to lower the morale of the enemy soldiers and to influence them to stop fighting. Less tactical and more indirect in effect was the spreading of the “true” battle picture and of the U.N. aims of peace, unification, and reconstruction.

Before the Korean conflict, details for a well-honed, coordinated operation had not been thought out carefully. Thus, only at the tactical level—the combat operation at or near the front line—did the approach taken show improvement over World War II.

When North Korea attacked South Korea, the only operational psywar troop unit in the Army was at Fort Riley, Kansas. The unit, sent to Korea in fall 1950 as the 1st Loudspeaker and Leaflet Company, was the Eighth Army’s tactical propaganda unit during the war. Loudspeakers on vehicles and aircraft also disseminated propaganda.

General Matthew B. Ridgway, Eighth Army commander in Korea, was enthusiastic about psychological warfare and frequently passed along suggestions to the psychological warfare department for consideration. He once suggested he would prefer greater use of art on leaflets, especially those depicting to the enemy the horrors of their comrades’ deaths on the battlefields.

One such message, disseminated by artillery and aircraft bombardment, proclaimed:

Comrades! Soldiers of the North Korean Army. . . . U.N. airplanes are overhead prepared to strike your positions. They are loaded with rockets, napalm and MG. U.N. artillery is sighting on you. At my command they will bring you death. . . . You have seen your positions littered with the burned, blackened, and shattered bodies of your buddies after our planes and artillery come down upon you. You have seen your buddies with their clothes and bodies blown limb from limb by our shells. . . . Even if you are not hit directly, your nose and ears will bleed, your eardrums will be broken, your organs deranged, and your minds will cease to function. . . . Raise both hands high over your head and walk in the open toward U.N. lines. . . . You are guaranteed good treatment. . . . Act now. You have five minutes.

Some leaflets promised medical treatment for frostbite, undermined faith in officers, and similarly instilled fear for soldiers’ safety. Other themes for tactical operations told of the mounting enemy dead and the U.N. materiel superiority. Many enemy POWs claimed that the signature of General MacArthur on a surrender pass convinced them that promises of good treatment would be honored.

Secretary of the Army Frank Pace, Jr. believed Korea offered an “especial opportunity for highly profitable exploitation” of psychological warfare, and the secretary advocated “quality rather than quantity” in producing leaflets and radio broadcasts. In spring 1951, strategic plans were under way to double an effort of about 13 million propaganda leaflets a week and to augment thirteen hours of daily radio broadcasts in Korean by adding shortwave broadcasts in Chinese to Chinese troops in Korea and Manchuria. Aircraft by then were flying leaflet missions nearly every day of the week. Leaflets and loudspeakers were credited as a factor in a heavy increase in prisoners as the Korean War moved into its second year. Pace considered psywar as the “cheapest form of warfare,” and Ridgway, when he moved into charge in Tokyo of the Far East command, wanted personnel of “integrity and intellectual capacity” for a psywar planning group.

The 1st Radio Broadcasting and Leaflet (RB&L) Group became the operating agency for psywar in the Far East after it arrived in Tokyo in summer 1951, some of its key personnel having been rushed over earlier to become immediately operational. Some group members were young draftees who were graduates of journalism schools. Others had art backgrounds or experience in advertising, radio, or newspapering. This background may well account for the unparalleled visual quality of U.N. Korean War leaflets. The unit had an international flavor because some of its members were native linguists. To facilitate radio and leaflet propaganda and reach all educational levels of the target audience, members of the group eventually compiled a 4,000 character Chinese-English dictionary used to produce effective propaganda material. Translators often had laughed at errors in scripts caused by the Americans’ failure to understand the language nuances and the cultures of their targets. Some expensive printshop equipment shipped to Japan was stored in Yokohama because the Japanese printing industry was well developed and no need existed to set up a separate printing plant. The group supervised a radio network known as the “Voice of the United Nations” and produced millions of leaflets disseminated by aircraft and artillery shells. Its radio operations in Korea were under control of the 1st RB&L Group’s Mobile Radio Broadcasting Company.

By the end of the war, more than 2.5 billion leaflets had been dropped over enemy troops and civilians in North Korea. The usual procedure was as follows:

Psywar officers in the field would decide on a drop in a particular sector. They would telephone the Tokyo psychological warfare office, giving the general content thought desirable and where the drop should occur. The Tokyo personnel took the leaflets out of existing stocks or printed them for the occasion. From the printing plant the leaflets were taken to air bases and loaded into aircraft for drops or shipped to Korea for drops by Korea-based aircraft.

Interrogation of enemy soldiers showed about one of three were to some degree influenced to surrender by the leaflets. Interrogation of civilians in North Korea and the parts of South Korea that had been occupied by Communist forces revealed that the radio programs also reached a considerable audience and stirred some civilian opposition to the red regime. Native Koreans served as announcers.

About 200,000 radio sets were in Korea before the fighting broke out, about one set per 100 people. A shortage of receivers and frequent disruptions of electrical power limited the effectiveness of radio operations. A few North Koreans owned two radios. Sometimes they would tune a radio in the front of a home to a Communist station and in another part of the house clandestinely listen to the U.N. broadcasts.

For all this apparent success, division and corps commanders had to be indoctrinated to the value of working with the psychological warfare section.

Brigadier General Robert McClure, chief of the psychological warfare division of the Army, operated out of Washington after his office was created in late 1950 after the war began. The Army, because of the impetus of the war, Cold War tensions, and Secretary Pace’s persistent pressure, had created an unprecedented staff organization in the Pentagon—the office of the chief of psychological warfare. A “true believer” in psywar, McClure had emerged from World War II as the Army’s expert in the new field. Under Pace, the general created a staff responsible for psychological and unconventional warfare. Despite the “hot war” in Korea, the driving factor in the Army’s support was a desire for guerrilla capability in Europe to retard a Soviet invasion, if it should occur. McClure convinced the Army to create a separate Psychological Warfare Center in 1952 at Fort Bragg, N.C., from which the Army Special Forces training facilities would emerge.

Photo Caption: The interior of a C-47 aircraft specially equipped to broadcast surrender appeals to Chinese Communist troops. Members of the 8th Army Psychological Warfare Section are standing near the loud speakers.

McClure campaigned to improve the air support he claimed psywar lacked in its initial year in Korea. But in the ten days after the successful surprise landing at Inchon on September 15, 1950, accompanied by the simultaneous breakout from the Pusan perimeter, thirteen B-29s had bombarded the North Koreans with leaflets inviting them to surrender. Operations officers at FEAF thought the support effort excessive, but Air Force intelligence reported the missions as “highly profitable.” Near Seoul on September 23, a total of 104 enemy Koreans surrendered together, each man carrying one of the “safe-conduct” passes dropped by the Superforts.

U.S. aircraft dropped warning leaflets before bombing industrial and factory areas in the North, giving workers time to flee, though some were ordered to stay on the job and not read the leaflets.

B-29 crews called the leaflet missions “paper routes.” Over friendly territory, the leaflets were dropped from low-flying planes in loosely wrapped bundles that fell apart as they descended. In the beginning the leaflet bombs were extremely unreliable, more than one-third failing to open. The supply at times ran out, and because of failures the coverage was less thorough than it might have been.

Drops over hostile territory used hollow aerial bombs, each with a capacity of 45,000 4-by-5-inch leaflets. Thirty-two bombs constituted an aircraft load. The bombs were released at 15,000 feet or higher, with fuses set to open them at 1,000 feet. Standard artillery smoke shells were converted to leaflet shells and dispersed by artillery in cooperation with combat operations.

In March 1951, a psywar leaflet urged guerrillas in South Korea to give up a hopeless fight. Translated, the message warned that “the mouse has gnawed at the tiger’s tail long enough.” Hard-hitting cartoons were also part of a propaganda effort aimed at an enemy whose foot soldiers usually had only a smattering of elementary education.

Within twenty-four hours after President Harry S. Truman announced U.S. troops would assist the invaded Republic of South Korea, leaflets were dropped over Korea telling of the decision. And within the next twenty-four hours, radio broadcasts from Tokyo were beamed toward Korea, psywar becoming the first weapon used by the United Nations north of the 38th parallel.

Prior to the outbreak of hostilities, Major General Charles A. Willoughby, General MacArthur’s assistant chief of staff, G-2, had set up a small planning group to carry out psywar in the event of an emergency. The original planning group of six had grown to thirty-five by December 1950.

Two C-47 aircraft were made available to the Eighth Army and X Corps to broadcast surrender messages over airborne loudspeakers. The Air Force had failed to develop loudspeaker aircraft before the Korean War and the two that were finally put into service had the loudspeakers mounted to project slightly from the doors, pointing to a 45-degree angle downward when the planes flew straight and level. In May 1951 the speakers were moved to the bottom of the planes so they could point them directly at the ground with less danger to the craft. Psywar staff officers were the link between the operational forces and higher headquarters.

By April 1951, psywar officers in the field tried to make greater use of tactical aircraft, and coordination efforts improved in leaflet drops, loudspeaker missions, and air missions.

In March 1953, the Fifth Air Force in cooperation with the Eighth Army began dropping a special leaflet that asked: “Where is the Communist Air Force?” The drops were made on enemy troop concentrations the Air Force attacked. Radio Seoul hammered the same theme.

On the night of April 26, 1953 two B-29s dropped more than one million leaflets along the Yalu River on the North Korea-China border, offering $50,000 and political asylum to each Russian, Chinese, and Korean pilot who would deliver his jet plane to Kimpo Airfield. The first man who delivered his plane would receive an extra $50,000. The offer became known, fittingly, as “Project Moolah” and was first conceived by a war correspondent in Seoul, according to one report; another account termed “Moolah” the product of the Harvard University Russian Research Center. Another half-million “reward” leaflets were dropped on the nights of May 10 and May 18 over Sinuiju and Uiju airfields, and radio stations beamed the “Moolah” offers in Russian, Chinese, and Korean language broadcasts.

But no Communist airman delivered a plane as a result of the “Moolah” broadcasts. A North Korean lieutenant who defected after the war with a MiG on September 21, 1953, claimed he had never heard of the $100,000 windfall he was to receive, according to Air Force intelligence. But a unit commendation issued by the Army to the 1st Radio Broadcasting and Leaflet Group in July 1954 gives the unit implied credit for the pilot delivering the undamaged MiG-15 fighter plane and cites the unit for “an ingeniously planned and capably disseminated propaganda broadcast” that materially assisted in destroying the morale of enemy troops, reducing greatly their effectiveness in combat. It may well be that the MiG pilot was reluctant to admit that he had brought over his plane and his person for crass monetary gain.

It is thought the Soviets may have withdrawn their pilots after the “Moolah” offer. An unlocated radio transmitter began to jam only Russian-language broadcasts of the reward offer, and after May 8 most MiGs sighted by Sabres bore Chinese or North Korean insignia. Earlier in the year most MiGs had borne the plain red stars of the Soviet Union.

The 98th Bomb Wing at the end of the war was using leaflet casings of about 500 pounds when loaded. About one million individual leaflets could be distributed nightly by a single B-29 Superfort. The big planes used radar to rain the leaflet clusters at night and in bad weather on towns, villages, and military billeting areas.

Weekly plans spelled out psywar themes for radio, leaflets, and other media. One major theme was that the Communists sought to enslave all Korea and to exploit its economy for their own gain. Another was that all the free nations of the world, through the United Nations, supported the Republic of Korea in opposing Communist aggression.

The reliance on C-47 transport aircraft as a way of disseminating leaflets and the use of voiceplanes at the tactical level were uncomplicated by enemy air or antiaircraft action.

William I. McCorkle


Andrews, T. G., et al. An Investigation of Individual Factors Relating to the Effectiveness of Psychological Warfare (1952).

Daugherty, William, in collaboration with M. Janowitz. A Psychological Warfare Casebook (1958).

Hansen, K. K. “Psywar in Korea,” typescript, Office of the Joint Chiefs of Staff (n.d.).

Kahn, Lessing, and Julius Segal. Psychological Warfare and Other Factors Affecting the Surrender of North Korean and Chinese Forces (1953).

McLaurin, R., ed. Military Propaganda: Psychological Warfare and Operations (1982).

Mossman, Billy. EUSAK Combat Propaganda Operations, 13 July 1950 -1 September 1952, Far East United States Army Forces, 3rd Historical Detachment (n.d.).

Pease, Stephen E. Psywar: Psychological Warfare in Korea, 1950-1953 (1992).

Reprinted with permission from The Korean War: An Encyclopedia, edited by Stanley Sandler and published by Garland Publishing, Inc.