US Strategic Command’s commander, General Anthony Cotton, labels this issue the three body problem. As nuclear strategy experts suggest, American deterrence capabilities and overall numbers both matter.

Patrick McKenna and Dylan Land’s “Don’t Get Lost in the Numbers: An Analytic Framework for Nuclear Force Requirements Debates,” details four essential variables for right-sizing the arsenal: risk management, deterrence and assurance goals, force use guidelines, and operational constraints. This article will unpack the matter of risk management.

Risk management issues permeate virtually every decision about nuclear posture and arsenal right-sizing. The perspectives of tolerable nuclear risks held by America, this country’s adversaries, and this country’s allies all matter to effective global nuclear peacekeeping.

Deterrence theorists rightly argue that the US should start by understanding exactly what each adversary values most and their goals. This information is useful in determining what to hold at risk—the high value assets to target. The total number of those targets is an essential input to arsenal right-sizing.

Political and fiscal compromises have a major impact on arsenal size as well. For the United States, the finite capacity of the defense industrial base is a major current constraint. The less money available to sustain America’s triad, the greater the risk that the force structure is not adequate to deter adversaries and assure allies. The weaker the political will to resist coercion, and to retaliate in kind to any nuclear attacks, large or small, the less successful is deterrence and assurance.

Similarly, the less the production capacity of the defense industrial base, the less the US is able to implement on a timely basis whatever types and numbers of delivery vehicles and warheads are the chosen arsenal size and force structure.

Since nuclear deterrence has never failed, analysis is necessarily prospective and does not rely on large quantities of data or past experience. Instead, there is a reliance on inferences from military and political history, combined with playing out, on paper, the aftermath of a nuclear war.

The United States is now dealing with the unpleasant reality that any significant expansion in the nuclear arsenal is accomplished much less rapidly than adversaries can grow and strengthen their own arsenals. Actuarial science suggests that guarding against catastrophic failures calls for worst-case planning. Given the catastrophic results of nuclear warfare, right-sizing the nuclear triad must deter all adversaries simultaneously. This includes accounting for the instance in which China, North Korea, and Russia collaborate to coerce or attack the United States. Should they ever take the gamble to launch a nuclear attack, American deterrence has utterly failed.

An upper bound on American deployed warheads is the sum of what is needed to deter each adversary in isolation. This is because should US Strategic Command deploy enough nuclear weapons to simultaneously hold Chinese, North Korean, and Russian targets at risk, deterrence is likely to hold. Keep in mind, there is no historical example to suggest that all weapons will strike designated targets.

Thus, the fewer weapons there are to strike targets, the greater the risk of deterrence failure. This leaves the old pejorative, “We will make the rubble bounce,” important when considering that probability of target destruction is certainly much lower than many believe.

As with other inputs to triad right-sizing, wherein less of an important resource increases the risk of deterrence failure, the more the total number of deployed nuclear warheads falls short of the upper bound mentioned above, and the greater the risk becomes that one or another scenario of adversary coercion or attack will occur and possibly succeed.

But assuming the US fields a large enough and modernized arsenal, there is a disincentive for any single attacker to strike the United States and for a second adversary to wait, assess the damage, and perhaps complete what the initial attacker did not. There is also a disincentive for all adversaries to collaborate in a unified attack. Absent a large American arsenal, such considerations become more viable.

Risk is relative. There is seldom one right answer when many limited resources are being competed for, while the nation must also address other priorities besides the all-important national defense. But to go very far below the upper bound of the total number of high-value targets risks deterrence failure. Any resource savings are short-term and illusory. The costs of deterrence failure vastly eclipse any imagined benefits to a too-small arsenal.

Only further research and development, strategic planning, intelligence analysis, and open debate can lead to a sound consensus on exactly how big the nuclear arsenal needs to be during the risk-laden years that lie ahead. There is no time to waste.

Joe Buff is an experienced actuary with four decades of experience. Views expressed in this article are the author’s own.

Nuclear Right-sizing was originally published on Global Security Review.

Several months ago, the Bulletin of Atomic Scientists published an article by Zak Kallenborn in which he defended nuclear weapons and their utility. Rebuttal articles published made two fundamental arguments. First, realism predicts the unavoidability of war, which requires the elimination of nuclear weapons. Second, deterrence is unreliable because previous close calls predict future failure.

The authors believe that reducing nuclear weapons to [near] zero limits the danger in inevitable future wars because future cheating or proliferation would only take place in small numbers, thereby limiting the damage of nuclear use. History and game theory prove this argument dangerously flawed.

For two millennia, major power wars occurred several times per century. Oxford’s Max Roser charts this bloody cost over the past 600 years. In that time 5–10 people per 100,000 population died in these wars, most of them civilians. In the past century deaths topped 100–200 deaths per 100,000 population.

Then after World War II something happened. Over the past seven decades this death rate has plummeted 99 percent to near zero (0.1/100,000 population). This is in spite of small spikes, which are attributable primarily to ethnic genocide in the (non-nuclear) global South. The world did not magically become more pacific. It built nuclear weapons.

The same abolitionists who criticize Kallenborn are horrified by the scale of the slaughter in Gaza and Ukraine. Over 315,000 Russian and 31,000 Ukraine troops are dead in Ukraine and 12,000 Hamas fighters in Gaza. Nuclear abolitionists fail to grasp, this is a mere drop in the bucket compared to great power war.

For example, during World War I, there were 480,000 casualties in 7 days at the Battle of the Marne. There were 848,614 casualties at Passendaele and another 946,000 at Verdun. During World War II, more than 61,000 British civilians died in the Battle of Britain. Over 83,000 British and American airmen died over Germany

European deaths during World War II are estimated at 28.7 million people. Great-power war gave rise to Joseph Stalin and Adolph Hitler, who exterminated over 30 million people between them. Stalin’s genocide of  3.5 to 7 million Ukrainians in 1932 and 1933 is the historical context for Ukrainian resistance today.

When it comes to killing civilians, the Japanese beat Stalin and Hitler combined. They killed over 300,000 Chinese during the “Rape of Nanjing.” China suffered over 35 million casualties during the Japanese occupation. When atomic bombs dropped on Japan, the Japanese army was still killing an estimated 250,000 Chinese every month.

During World War II, conventional bombing raids killed more civilians in a single night than both atomic bombs. In the Dresden firestorm, caused by allied conventional bombing, 135,000 Germans were incinerated. The ability of today’s conventional weapons is even greater.

The only answer to the horror of war is to keep the peace through effective deterrence.  To do this, those who would wage war must know the reward does not justify the risk. Deterrence does this at every level of conflict.

Arms control treaty regimes, the source of stability for nuclear disarmament advocates, are largely a failure. Despite the existence of the Treaty on the Non-proliferation of Nuclear Weapons, Iran, Iraq, Israel, Libya, North Korea, Pakistan, and South Africa all sought or obtained the bomb. The Comprehensive Nuclear-Test-Ban Treaty also failed to stop nuclear testing, with the violations of India, North Korea, and Pakistan. China, Egypt, Iran, Israel, Russia, and the United States have either not signed or ratified the treaty.

Russia breached the Intermediate-Range Nuclear Forces Treaty during the Obama administration and then suspended participation in New START in 2023. As a result, for the first time in five decades, there is no nuclear arms limitation treaty between the United States and Russia/Soviet Union. Russia already maintained a policy of escalate to de-escalate during New START negotiations and, in fact, Chinese, North Korean, and Russian military doctrines all contemplate nuclear warfighting across the spectrum of conflict.

Deterrence is working every day and is not reserved for discussions of nuclear war. As China, Iran, North Korea, and Russia coalesce in an authoritarian coalition, deterrence remains the last best hope for averting war. It works along the entire continuum of conflict, reducing the likelihood of war. In short, nuclear weapons save lives.

Colonel Kirk Fansher (US Air Force, Ret.) is a Senior Fellow at the National Institute for Deterrence Studies. The views expressed are the author’s own.

Why Nuclear Weapons Abolition Will Kill Millions (Again) was originally published on Global Security Review.