There are US defense and foreign policy experts who assert that history proves the United States should retain the option to use nuclear weapons to prevent non-nuclear attacks against the United States and its allies. The evidence supporting that assertion is questionable.
The historical record in Europe is ambiguous. Although there was no Soviet attack against Western Europe during the Cold War it is difficult to prove US threats to use nuclear weapons were responsible for preventing it. There is convincing evidence, however, that the fear of US nuclear weapons failed to deter the People’s Republic of China (PRC) from attacking US forces in Korea.
PRC Leaders Debate the US Nuclear Threat
US President Harry Truman’s June 27, 1950, statement on US involvement in Korea simultaneously reversed previously announced US intensions to avoid military intervention in the Chinese civil war and to withhold US military aid from the Chinese government on Taiwan. On July 13th the Central Military Commission (CMC) of the newly established People’s Republic of China (PRC) met to discuss the possibility of US attacks on the Chinese mainland. It decided to send PRC troops to defend the northeast border with Korea.
On July 31, a few weeks after the CMC meeting, the US Joint Chiefs of Staff informed the commanding US general in Korea, Douglas MacArthur, that “in accordance with previously arranged long-term plans” the non-nuclear components for ten atomic bombs would be placed in storage on Guam and that the nuclear components could be made available within 72 hours of a presidential authorization to use nuclear weapons.
It is unclear if PRC intelligences services were aware of this development, but the Chinese soldiers sent to the border with Korea were deeply concerned about the possible US use of nuclear weapons, so much so that their political commissar, Du Ping, reported psychological problems debilitated about 10% of the force. The Political Bureau of the People’s Liberation Army (PLA) put together a comprehensive propaganda campaign to try to reassure the troops that people, not weapons, determined the outcome of wars.
The Chinese Communist Party Central Committee met regularly throughout the late summer and early fall to debate providing military assistance to North Korean forces. It discussed concerns about the possible use of US nuclear weapons. Senior Chinese leaders opposed to PRC involvement in the Korean conflict argued the United States might retaliate with nuclear attacks against the Chinese mainland. PLA General Lin Biao, who led communist forces in northeast China during the civil war against the nationalists, refused Chairman Mao Zedong’s request to take command of a PRC force for Korea and warned that US nuclear strikes against key urban and industrial centers would prove more than the newly established government of the People’s Republic could bear.
Mao settled the issue in early September by announcing that if US forces crossed the 38th parallel—the dividing line between North and South Korea established at the end of WW II—the PRC would intervene. MacArthur landed at Inchon shortly afterwards and crossed the 38th parallel on October 7th. Mao gave the order to enter the war the following day.
On November 25th the PRC forces Mao sent into Korea began a major military offensive that surprised MacArthur and alarmed the US public. On November 30th President Truman made the US threat to use nuclear weapons in Korea public during a press conference. The PRC offensive continued, however, and was successful in pushing U.S. forces back to the 38th parallel by mid-December.
The historical record in this case shows that PRC leaders believed a US nuclear attack was possible but the threat did not prevent them from entering the war or deter the continuation of a major military offensive against US forces to achieve their war aim.
The Long-Term Influence of U.S Nuclear Threats in Korea
The United States did not use nuclear weapons in Korea but the credibility of the threat intimidated and divided Chinese decision-makers. The debate over how to stand up to what they described as nuclear blackmail, rather than nuclear deterrence, had a direct effect on the young communist government’s long-term planning. In May 1952, as the US expanded its strategic bombing campaign to include dams and power plants along the Yalu river near the Chinese border, PRC Premier Zhou Enlai met with generals Zhu De, Peng Dehuai and Nie Rongzhen to discuss defense expenditures under the First Five-Year Plan, which would set PRC priorities for national construction during the period from 1953-1957. The question of beginning a nuclear weapons program was one of the most hotly debated issues on the agenda.
Zhou was concerned the new government did not have the human, technical or natural resources to build the bomb. But because of the experience with US nuclear threats during the Korean war, many Chinese leaders agreed that if a thorough feasibility study indicated it was possible, the PRC should make the attempt. Two years into the five-year plan, not long after uranium was discovered in China’s southwest, an expanded session of the Chinese Communist Party Central Committee decided on January 15, 1955 to greenlight a nuclear weapons program. It would consume the lion’s share of the PRC’s research and development budget for the next three decades.
Today one of the arguments against using nuclear weapons to deter non-nuclear attacks is that it invites proliferation. It seems clear in this case, based on the available PRC historical materials, that US nuclear threats during the Korean War played a critical role in communist China’s decision to build the bomb.
Lack of comparable access to North Korean historical materials makes it difficult to know if its nuclear weapons program is rooted in the same war-time experience. But it’s not an unreasonable assumption.
The Chinese communist leadership’s response to US nuclear threats 60 years ago continues to inhibit international diplomatic efforts to stop North Korea’s pursuit of nuclear weapons today. On the one hand, its relationship with North Korea, forged during the Korean War and celebrated by Xi Jinping on its 60th anniversary, puts Chinese leaders in a unique position to influence North Korean behavior. The PRC certainly does not want another nuclear-armed state on its border. So many other nations, including the United States, expect Chinese leaders to use their influence to persuade their North Korean counterparts to dismantle their nuclear weapons program. But as noted in a 1995 Japanese Defense Agency (JDA) study of Japan’s nuclear options,
“Although North Korea’s nuclear development is like a dagger stuck to China’s throat, it has the same logical justification of China’s own nuclear development. China cannot condemn it. It is nothing other than an entanglement in one’s own net.”
Lessons for No First Use
The Korean War is not a minor outlier in the history of nuclear deterrence. It is a defining event that shaped the political and security contours of Asia during the Cold War with a legacy that remains relevant today. The US experience in Korea shows how attempting to use nuclear threats to deter large-scale conventional attacks can fail, and that one of the potential consequences of failure is nuclear proliferation.
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