In a recent article for the Heritage Foundation, Robert Peters argues that the United States should take the necessary steps to prepare to resume nuclear weapons testing. It triggered heated debate in the nuclear policy community, which has been seething since Robert O’Brien, President Trump’s former National Security Advisor during his first term, made similar arguments in Foreign Affairs in July.

While credible critiques state U.S. nuclear testing would permit Russian and Chinese testing in kind, erode nonproliferation norms, and is unnecessary from a technical perspective, all miss the logic of the argument made by Peters and O’Brien. That is, nuclear tests have deterrence value in times of rising tensions. As such, the debate’s pertinent question is whether nuclear tests are credible tools to demonstrate resolve during a crisis. The answer is a resounding no.

Lack of Historical Precedents

The balance of resolve weighs heavily on the minds of policymakers in times of rising tensions. For example, documented conversations between U.S. policymakers during the Berlin Crisis between 1958 and 1961 overwhelmingly reference the need to demonstrate resolve on Washington’s willingness to use nuclear weapons.

Indeed, a crisis would dissipate if the actual balance of resolve were clear to both actors. As a party to numerous crises during the nuclear age, it is quite illuminating that the United States has rarely, if ever, resorted to performative nuclear testing to demonstrate resolve. The Executive Committee of the National Security Council (EXCOMM) seldom discussed the role of Operation Dominic in demonstrating resolve during the Cuban Missile Crisis. Moreover, the four nuclear tests under the Dominic series in October 1962 seemingly had little effect on the Soviet decision calculus during the crisis. Likewise, EXCOMM did not take a keen interest in the two Soviet nuclear tests conducted during those 13 days. The Cuban Missile Crisis demonstrates the peripherality of nuclear testing in shaping perceptions of the balance of resolve, contrary to the claims made by Peters and O’Brien.

The Empty Promise of Nuclear Tests

There are several reasons why nuclear testing has little influence on the balance of resolve. First, a nuclear test signals capability credibility as opposed to crisis commitment. It is for this reason nascent nuclear-weapon states are more prone to conducting tests. North Korea uses tests to demonstrate its capabilities to ensure its deterrent is seen as credible by adversaries who question its effectiveness. In contrast, the U.S. nuclear arsenal’s ability to inflict devastating damage on Moscow or Beijing is unquestionable to anyone with a pulse. If Peters and O’Brien are interested in shaping adversarial perceptions of U.S. resolve during a time of crisis, it is unclear how a demonstration of U.S. nuclear capabilities via a nuclear test, which is already understood by our adversaries, achieves that mission.

Second, nuclear tests may cause a domestic response that degrades an actor’s resolve. Public pressure, media hysteria, or even protests against a crisis that precipitated a nuclear test could force policymakers to recalculate their resolve. This is likely why U.S. policymakers often downplay military tests as “routine” and have historically refrained from such performative measures in times of crisis. If Peters and O’Brien are interested in preserving U.S. policymakers’ levels of resolve in times of crisis, then it is unclear how nuclear tests achieve that mission.

Third, it’s not clear whether adversarial perceptions of the balance of resolve are at all mutable by nuclear tests. North Korea’s nuclear tests over the years have not altered Washington’s calculus on Pyongyang’s willingness to use nuclear weapons if it’s attacked. Instead, tests calcify previously held U.S. positions on Pyongyang’s resolve. In that way, nuclear tests can be understood under a longer time horizon as part of a process that gradually cements adversarial perceptions instead of a discrete tool that can be used in a moment of crisis, as argued by Peters and O’Brien.

Right Idea, Wrong Prescription

Peters and O’Brien point out resuming nuclear tests for one valuable reason: the United States must be prepared to effectively communicate resolve in a new age of great-power competition. As the United States has not tested a nuclear weapon in over 30 years, it makes sense that one would see a resumption as a potential signal of U.S. resolve. Unfortunately, nuclear tests do not provide the benefits needed to be an effective signal of resolve.

The United States should utilize tried-and-true signals during times of crisis that do not risk violating nonproliferation norms, creating environmental hazards, or accelerating the likelihood that Russia or China will resume nuclear weapons testing. These signals include increasing the readiness of U.S. armed forces, launching unmanned nuclear-capable missiles, and forging firm diplomatic messaging campaigns that extend off-ramps. If Washington seeks to bolster adversarial perceptions of resolve in times of crisis, it must work to adapt these traditional signals to 21st-century challenges instead of reviving a relic from the bowels of the Cold War.