[Insight & Opinion] The Russia-Ukraine War Shows the U.S. Nuclear Umbrella Cannot Be Trusted

Ukraine Gave Up Its Nukes Trusting U.S. Promises
Missile Strikes on Russian Mainland Also Prohibited
Tangible and Intangible Disadvantages for Non-Nuclear States

The Russia-Ukraine war conveys an uncomfortable truth to South Korea: that "the U.S. nuclear umbrella cannot be fully trusted." When Ukraine gained independence from the Soviet Union in 1991, it possessed around 1,800 Soviet nuclear weapons. Trusting promises from the U.S. and others under the "Budapest Memorandum on Security Assurances," Ukraine gave up its nuclear arsenal. The result is the current devastation of war and territorial loss. Ukraine’s case eloquently demonstrates that "the only protection against nuclear-armed states is possessing nuclear weapons oneself." It reveals that "a nuclear umbrella cannot substitute for nuclear possession."

The illusion of the nuclear umbrella is confirmed by various circumstances in the Russia-Ukraine war. Ukraine has suffered enormous damage from this conflict. Hundreds of thousands of soldiers and civilians have been killed or injured. The population has decreased by 8 million due to displacement abroad. Eighteen percent of the territory has fallen into enemy hands. The national economy has contracted by tens of percent.

Russia has bombarded Ukraine’s major cities, industrial infrastructure, and military forces with missiles, aerial bombs, and cluster munitions. From Ukraine’s perspective, to reduce damage, it must target the bases and facilities deep inside Russia from which these missiles and aircraft are launched. If Kyiv is struck, Moscow must be punished in return.

However, while the U.S. has provided Ukraine with fighter jets and missiles, it has prevented Ukraine from using them to attack Russian territory. This has effectively tied Ukraine’s hands. Why does the U.S. do this? Because it fears a chain reaction: "Ukraine attacks Russian mainland → Russia launches nuclear attack on Ukraine → U.S. (NATO) retaliates with nuclear attack on Russia (nuclear umbrella provided) → Russia retaliates with nuclear attack on U.S. (NATO)."

In conclusion, the U.S. has sought to eliminate any possibility of having to extend its nuclear umbrella to Ukraine while conducting a proxy war against Russia through Ukraine. To this end, it imposed a war rule unilaterally unfavorable to Ukraine: "No use of U.S.-made fighter jets and missiles for attacks on Russian mainland." This kind of tangible and intangible disadvantage forced on a non-nuclear country may well be the true nature of the nuclear umbrella.

President Yoon Suk-yeol and U.S. President Joe Biden made the "Washington Declaration" last April, claiming that the U.S. nuclear umbrella has been strengthened. However, unusually, this declaration included South Korea’s obligations under the Nuclear Non-Proliferation Treaty. There has been much criticism that "the U.S. focused on suppressing South Korea’s autonomy to arm itself with nuclear weapons without providing anything substantial." Since this declaration, discussions on nuclear fuel reprocessing and nuclear submarine construction have disappeared. Instead, the U.S. has acted as an obstacle to South Korea’s export of Korean-style nuclear power plants.

Article 4 of the "Comprehensive Strategic Partnership Agreement" signed between North Korea and Russia in June states that "if one party is in a state of war, the other will provide military assistance by all means." This increases the possibility of Russian intervention in a conflict between South and North Korea. If a conflict breaks out between China and Taiwan, it could also spread to the Korean Peninsula. There is a taboo question domestically: "Does the U.S. nuclear umbrella for South Korea also apply to nuclear attacks on South Korea by Russia or China?" The U.S. cannot answer.

As in Ukraine’s case, non-nuclear states cannot respond in kind in conventional wars against nuclear-armed states. The only way to deter an enemy from daring to attack Seoul, semiconductor complexes, and South Korean military units is to possess nuclear weapons independently.

Ukraine’s territorial loss is not someone else’s problem for us. For South Korea, surrounded by North Korean, Chinese, and Russian nuclear weapons, nuclear sovereignty is a "card directly linked to survival that must not be easily abandoned." To achieve this, South Korea must speak up to the U.S. and prepare all necessary means.

Heo Man-seop, Professor at Gangneung-Wonju National University