Nuclear taboo

The nuclear taboo is the idea that an international norm exists which prohibits the use of nuclear weapons. While many experts agree that this norm is real, not everyone is convinced. The term was brought into wider use by scholar Nina Tannenwald, who described it in her 1999 article as a practical ban on being the first to use nuclear weapons.

According to this concept, there is a shared belief that using nuclear weapons is both illegitimate and immoral. This belief is offered as a reason why no nuclear weapons have been used in war since World War II. It contrasts with other explanations for nuclear nonuse, such as rational deterrence theories like mutually assured destruction, or social arguments that using such weapons would violate international law.

Tannenwald has noted that the nuclear taboo shares many features of a taboo in general: it is a prohibition, it involves danger, and it carries expectations of terrible consequences or punishment if broken. It also acts as a "bright line" norm—once crossed, the world enters unknown and unimaginable territory. Additionally, the taboo works against the temptation leaders might feel to use nuclear weapons as the "ultimate weapon," reminding them of the dangers involved.

Definitions

A textbook on strategy defines the taboo as the view that using nuclear weapons is so shameful and immoral that states would avoid it, fearing they would become international outcasts, even among allies. Another academic, Joshua A. Schwartz, has defined it as the perception that nuclear use is so morally repulsive that policymakers and the public do not even consider it.

Debate over the concept

The existence of this taboo is debated. Tannenwald argues the norm developed during the early Cold War, pushed by anti-nuclear movements and non-nuclear states, and was reinforced by U.S. and Soviet restraint after the 1962 Cuban Missile Crisis. However, critics point out that there have been no truly hard cases where a nuclear-armed state chose defeat over using its arsenal, so the taboo remains unproven.

In 2024, Schwartz argued the taboo does not exist, citing evidence that policymakers have seriously considered using nuclear weapons on multiple occasions. He also pointed to opinion polls showing majority or near-majority public support in China, France, Israel, the United Kingdom, and the United States for using nuclear weapons in certain situations.