Tactical Nukes: One Little Nuclear Weapon Can Ruin Your Whole Day

Different Size Nukes

Nuclear weapons can vary tremendously in size. The power of an explosion from a nuclear weapon is called its “yield”, measured in “TNT equivalents,” meaning how much TNT would produce the same size explosion. The bombs dropped on Japan in World War II had yields of approximately 15 kilotons of TNT, or 30,000 pounds of TNT. Thermonuclear weapons, also called hydrogen bombs, can be theoretically made to have almost unlimited yield. The so-called “Tsar Bomba”, detonated by the Soviet Union in 1962, was the largest ever tested, at 50 megatons, or 100,000,000 pounds of TNT. But regular atomic bombs can have relatively small yields, down to one ton and below.

Are tactical nukes the same thing as smaller yield nukes?

While they are often relatively small in yield, size isn’t the key feature. The thing that defines what a tactical nuclear weapon is is its intended purpose. Tactical nuclear weapons are designed to be used on the battlefield—in “tactical” situations, much as artillery is used. Other names include “non-strategic”, “theater”, or “battlefield” nuclear weapons. They stand in contrast to “strategic” nuclear weapons, which are meant to be used to attack an enemy’s cities, military installations, or nuclear weapons facilities. Strategic nuclear weapons are the warheads on intercontinental ballistic missiles (ICBMs); they also can be delivered by submarine-launched missiles or from long-range bombers. Another way of looking at these differences is that tactical nukes are designed for short-range use, typically meaning ranges of less than 300 miles, whereas strategic nukes are used over much greater distances.

Because the targets of strategic nuclear weapons are typically large, these weapons usually have greater yields. Today’s strategic US nuclear arsenal has warheads with yields ranging from 90 to 450 kilotons. In contrast, most tactical nukes have smaller yields, usually below 20 kilotons, sometimes much lower. You can find the US military’s definitions of tactical and strategic nukes in the “Department of Defense Dictionary of Military Terms”.

Arms Control Treaties

All existing arms control treaties only deal with strategic weapons. Some people have chosen to use the definition of tactical nukes as all nuclear weapons are not covered by strategic arms control treaties (like START: STrategic Arms Reduction Treaty).

Aren’t Tactical Nukes Safer?

No! They are typically smaller, but in some ways, they are more dangerous. Because they are often stored close to potential battlefields, they are more vulnerable to theft. More significantly, many perceive tactical nukes as more usable, which means the threshold for their use is lower. And control of the use of these forward-based weapons is in the hands of local commanders, not Washington. Of course, proponents say that their use would be limited to the battlefield, but there is no way to assure that is the case.

What are examples of tactical nukes?

The U.S. has many “dial-a-yield” or variable yield warheads, where the actual yield can be adjusted for different purposes. For example, the B61 warhead has a Mod-10 model that can be selected to give yields of 0.3, 5, 10 or 80 kilotons. In the U.S. military, most tactical nukes are gravity bombs. But the Navy has recently introduced tactical warheads on sub-launched missiles. Until now, these subs only carried missiles with strategic warheads; either the W76-1, with a yield of 90 kilotons, or the W88, with a yield of 455 kilotons. But in 2019, they began deploying the W76-2 on some of their missiles, with a yield of 5-7 kilotons. Many other platforms have also been employed for tactical nukes, including as warheads on cruise missiles, actual artillery shells, mines, torpedoes, and backpack nukes.

How many tactical nukes are there?

The U.S. at one time had thousands of tactical nukes, including novelties like the Davy Crockett gun that fired a shell with a 20-ton yield. The numbers decreased considerably after the 1960s as the focus became more on deterrence. The biggest decrease came in the early nineties, led by Presidents George H.W. Bush and Mikhail Gorbachev.

The precise numbers of tactical nukes are hard to pin down because countries don’t like to release the data. The use of variable yields further muddies the water. Currently, the US has 230 B-61 gravity bombs designed to be used with a variety of planes; currently, 100 of these are overseas at NATO bases. These bombs have variable yields, of from 0.3 to 170 kilotons. The basing of American nuclear weapons in NATO countries, notably Turkey, has been criticized as dangerously insecure. The Navy is believed to have about 50 of the new lower yield W76-2 warheads.

Do other countries use tactical nukes?

Other countries rely much more on tactical nukes. About 30-40% of warheads in the US and Russia fall into this category. Almost all of the nuclear weapons in France and China are short-range; that number is 100% in Israel, India, and Pakistan. Great Britain has none; the numbers in North Korea are not known.

“Escalate to De-escalate”

You may have heard this phrase in relation to potential Russian nuclear threats in Ukraine. This refers to a doctrine of nuclear use promoted recently by Russia. According to this strategy, if Russia were to find itself overwhelmed on the battlefield and in danger of losing, it could use a limited nuclear strike, presumably with battlefield nukes (i.e. “escalate” the war). This would theoretically cause their enemy to back off, or “de-escalate.” This strategy arose as Russian military leaders became convinced of the clear superiority of Western conventional forces and feared that only using nukes would counteract that superiority. Interestingly, during the early days of the Cold War, that same strategy was employed by NATO in the face of what were then superior Soviet conventional forces. The main fear here is that it assumes that the enemy would de-escalate, and not use their own nukes to retaliate, something that has never been tested.

This article from Scientific American unpacks the risks of tactical nuclear weapons related to the tensions between the United States and Russia. And here is a study from the Wilson Center on how Russia’s threat to use tactical nukes affects international stability.

Additional online Resources:

The Arms Control Center offers this fact sheet discussing the differences between ballistic and cruise missiles.

And here is a journal article about what might happen if tactical nukes are used in a war with Korea.