By Byron Adkins, Contributing Writer

The United States is giving a gift to its adversaries and undermining its own interests by pursuing tactical nuclear weapons. The United States’ pursuit of tactical nuclear weapons could destabilize East Asia, exacerbate tensions with Russia, or trigger an arms race among the great powers. Advocates claim that tactical nuclear weapons give the United States increased options to respond to aggression which has become a necessity to counter Russian doctrine. Even if this is true, utilizing tactical nuclear weapons still involves crossing the nuclear threshold and violating the nuclear taboo that some argue has prevented a great power war. The possession of lower-yield nuclear weapons and increased nuclear options can only increase the likelihood of their use and worsen the security dilemma.

Modernization of the nuclear arsenal is a goal listed in the 2017 National Defense Strategy, and Secretary of Defense Mark Esper has confirmed that modernization of the triad is a priority for the Department of Defense. In recent years, Russia has begun to increasingly field low-yield nuclear warheads capable of being used for diverse purposes. The United States has responded by fielding its first new nuclear weapon in decades to counter Russian capabilities. The underlying thought has been that if the United States or one of its allies were attacked by a tactical nuclear weapon, the United States would lack the flexibility for a proportional response. This was demonstrated in a recent wargame played out in Europe.

Tactical nuclear weapons were theorized to serve several purposes in U.S. nuclear policy throughout the nuclear age. These included lending increased credibility to extended deterrence, negating quantitative conventional inferiority and human wave tactics, and the aforementioned  flexibility in response. Tactical nuclear weapons were vastly curtailed after the 1987 signing of the Intermediate Range Nuclear Forces Treaty and the collapse of the Soviet Union. The United States withdrew from the treaty in 2019 after alleging Russia had been violating the conditions of the treaty since 2014. Tactical nuclear weapons have had a subsequent resurgence, both in possession and in the military doctrine of the countries that possess them. This resurgence has not been limited to the United States and Russia. China, Pakistan, and India have signaled interest in or a shift in doctrine to accommodate tactical nuclear weapons.

For all the theoretical benefits of possessing tactical nuclear weapons, there are also theoretical downsides that could prove costly and counterproductive to U.S. interests. The pursuit of additional tactical nuclear weapons will have implications for  the security dilemma. The security dilemma holds that security-seeking behavior (fielding tactical nukes) can make a state less secure by antagonizing other states, who then seek to increase their security. It is easy to see how a rapid build-up of tactical nuclear weapons could prompt a response. For example, if some of those tactical nuclear weapons are deployed on naval surface ships that operate near mainland China, it could cause China to expand its historically small and benign nuclear arsenal. A shift in the policies of our current adversaries, coupled with no meaningful arms limitation agreements could trigger an arms race that causes U.S. relative capabilities to drop.

The contemporary arguments for increasing the role of tactical weapons in U.S. nuclear policy create its own countervailing energy. If the reason for possessing tactical nuclear weapons is to provide more flexible options for their use, then logically the bar has been lowered for crossing the nuclear threshold. The conceptualization of an escalation ladder in which states differentiate between the use of tactical and strategic nuclear weapons is purely theoretical. There is no practical way to test the utility of such an idea. This means there is no certainty that a state involved in a tactical nuclear strike can be expected to retaliate differently than if receiving a strategic nuclear strike. With so much nuclear doctrine being purely theoretical, it should be accepted that any action that could lower the bar for nuclear use without knowing the consequences is an unwise policy. Additionally, increasing the likelihood of use for a class of weapons that are widely accepted as a deterrent in nature is contradictory.

Another reason the United States should avoid tactical nuclear weapons is its cost-benefit analysis. The estimated cost of planned nuclear modernization, of which tactical weapons are a part, is expected to be nearly $500 billion over the next decade. This is a substantial amount of money when considering that a nuclear weapon has not been used in warfare since 1945. It would be difficult to convince people that the nearly $500 billion is well spent on security while acknowledging the non-use underlying nuclear deterrence.

U.S. policymakers and defense officials should reconsider the inclusion of tactical nuclear weapons in the arsenal and doctrine. The risks of further proliferation, arms racing, and increased opportunities for use are a high price for having flexible options focused on a relatively weak Russia. These unnecessary risks also run counter to the nuclear deterrent theory itself. After all, if a deterrent weapon has to be used, then it has demonstrably failed its own purpose.

Byron Adkins is an Army Officer and current student at George Washington University’s Elliott School of International Affairs pursuing his M.A. in Security Policy Studies. His concentration is U.S. National Security and his research is focused on great power competition.