Will Russia use tactical nuclear weapons against Ukraine?

With Vladimir Putin suffering a series of humiliating setbacks in Ukraine, the Russian leader's threat to launch a tactical nuclear missile has plunged the world into its most perilous position since the darkest days of the Cold War. But what is a tactical nuclear weapon, what's the likelihood of one being used, and what can NATO do in response to the threat? New Atlas takes a look.

Putin's invasion of Ukraine is not only the biggest military conflict in Europe since the Second World War, it's also one that forced the world to face some very unpleasant truths that have all been largely forgotten in an age of complacency.

Peace is not a birthright

Modern Europe is based in large part on a simple consensus, which is that the purpose of society is to provide its members with the most peace and prosperity possible. These are very broad concepts and can hide some very unpleasant consequences. However, while prosperity has proven elusive in securing for all, peace in Western Europe has reigned for so long that it was taken as a given – even a birthright.

That idea of unshakable peace was very badly shaken when the Russian Army rolled into Ukraine in February 2022 with the goal of overthrowing the Kyiv government and replacing it with a regime friendly to Russia that would refuse NATO membership.

The envisioned blitzkrieg failed and the fighting collapsed into trench warfare, but within days of the invasion, Putin declared that Russia's nuclear forces were being placed on heightened alert and that he would launch nuclear weapons if NATO forces attempted to intervene in Ukraine.

Suddenly, Europe found itself hurled decades into the past as it faced not only the threat of nuclear arms in the hands of a hostile Eastern power, but a power that was on the march and waging tank and missile battles on NATO's doorstep. It wasn't on the scale of the Axis offensive or the feared Warsaw Pact armored advance envisioned in the 1980s, but it shook the complacency of Europe.

It's therefore small wonder that the NATO powers were expanding their forces and extending membership to previously neutral Sweden and Finland.

Needless to say, this is disconcerting for a continent where the average person was 13 years old when the Cold War ended and have grown up in a society where most people (and even leaders) had only the haziest notions about nuclear weapons, how they work, or how they'd be used.

As a result, much of the discussion about Russia threatening to unleash a tactical nuclear warhead has often been based on popular Cold War ideas of 75 years ago, misunderstandings about what is involved, and a general ignorance of history that is enough to raise eyebrows at the way the word "unprecedented" is bandied about as if nuclear saber rattling like the Cuban Missile Crisis or conflicts like the Falklands War or the Iraq Invasion had never happened.

What happened?

The question of how the whole mess in Ukraine happened is beyond the scope of this discussion. The reasons, whys, and wherefores of the situation are much more complicated than Putin suddenly getting an irrational yen to grab some lebensraum. It's a story of personal ambition, duplicity, deep-seated resentments, unresolved issues that date back centuries, a string of miscalculations, and, yes, Putin's villainy that form a Gordian knot that diplomats, historians, and military analysts will be teasing apart for decades.

However, the matter of tactical nuclear weapons in Ukraine is easier to understand. By the 1990s, US conventional military power and capabilities had reached a level unseen by any other fighting force in history as America emerged from the Cold War as the only hyperpower. In the Persian Gulf and in the Balkans, the ability of the US to perform precision strikes and maneuver forces on land, sea, and air across the globe as if they were a single unit made it capable of performing missions that were previously thought to require nuclear weapons or massive strategic forces.

In response to this, the Russian Security Council under the leadership of Putin, who was then the Council Secretary, developed the concept of escalation to achieve de-escalation. In other words, to respond to a threat of US or NATO intervention in Russian military operations, such as in Chechnya, by threatening nuclear retaliation to force the West to return to the status quo ante.

To do this, Russian planners developed a strategy of inflicting "tailored damage," where a threatened nuclear strike would inflict subjectively unacceptable damage on strictly military targets, but not enough to warrant an all-out counter attack.

This is why Putin played the nuclear card in February. There is no evidence that Russia was actually preparing its nuclear forces for a strike and things would have been left at that if Russia's plans hadn't gone south so fast or if Ukraine hadn't been able to use NATO-supplied advanced weapons to not only inflict heavy casualties on the Russian Army, but to recapture surprisingly large swaths of territory.

It really didn't help that Ukraine recaptured the town of Lyman on the very day that Putin declared the annexation of Donetsk, Luhansk, Zaporizhzhia, and Kherson after sham referenda or that Russia now faces continuing the war with raw recruits scooped up in a highly unpopular conscription.

These setbacks are not only humiliating for Russia, they are also potentially fatal for Putin in a very literal sense. His position is based on his personal strength balanced against the Russian oligarchs and losing the war in Ukraine could result in his exile, imprisonment, or an untimely "accident."

It's therefore a small wonder that Putin is now talking much more seriously about using a tactical nuke to at least ward off defeat.

What is a tactical nuclear weapon?

The first thing to get out of the way is that a tactical nuclear weapon isn't the same as the giant megaton-yield bombs capable of destroying entire cities that have terrified people for years in civil defense films and nightmare Hollywood features like Dr. Strangelove. Tactical nuclear weapons are not intended to spark off World War III. In fact, their purpose is precisely the opposite.

Tactical nuclear weapons, as the name implies, are designed for battlefield rather than strategic use. Put simply, these are very low-yield nuclear warheads that are used to counter a massive conventional force very quickly with a minimum of collateral damage to civilians and property in the vicinity.

The first of these weapons were developed in the 1950s by the United States, the USSR, Britain, and France in the expectation of giant battles of fleets of main battle tanks that were expected in Central and Eastern Europe if war broke out. The idea was that tactical nukes would be used by NATO to stop Warsaw Pact advances at strategic choke points, while the USSR incorporated the weapons into its strategy of turning Eastern Europe into one huge nuclear kill zone to protect the Soviet Union.

These weapons ranged from nuclear warheads with a yield of a fraction of a kiloton up to 50 kilotons. For scale, the Hiroshima bomb had a yield of about 15 kilotons, so some of the bigger ones were pretty destructive.

Tactical nuclear weapons come in a number of variants, including gravity bombs, short-range missiles, artillery shells, land mines, depth charges, torpedoes, and portable demolition charges for destroying tunnels, bridges, narrow passes, and viaducts.

The smallest tactical weapon was the US' Davy Crockett, which was a recoilless rifle weighing 108.5 lb (49.2 kg) and loaded with a 20-tonne (not kiloton) yield warhead that looked like a big iron egg with fins. Deployed from the 1950s to the '70s, it was designed to be carried in a Jeep by a small infantry team to quickly react to a surprise attack by setting up the rifle, firing at a range of 1.25 miles (2 km), and then running away very, very quickly.

How the lines of blurred

One of the problems with tactical nuclear weapons is that, over the years, the lines between tactical and strategic weapons have become increasingly ambiguous.

When hydrogen bombs were developed, strategic bombs were the very big ones and the tactical nukes were the very small ones. However, as technology progressed, conventional bombs became more powerful, with ones like the US Mother Of All Bombs (MOAB) yielding 0.011 kilotons. At the same time, conventional munitions became smarter and more precise, making them as effective as strategic nuclear weapons for much less explosive power.

Stockpiles

The world's nuclear stockpile today is a fraction of what it was during the Cold War, but the arsenals are still large. Russia has a total of about 6,200 nuclear warheads of which an estimated 1,912 are tactical weapons. These can be fitted to a number of platforms, but mainly on short-range missiles like the Kalibr (SS-N-30) or the Iskander M (SS-26 Stone) missiles, with a yield about a third of that of the Hiroshima bomb. How many of these are deployed, in storage, or inoperative isn't known.

In contrast, the United States has largely abandoned tactical nukes and only has about 500 deployed in bombs and Tomahawk cruise missiles (100 in Europe) and another 700 in storage. Meanwhile Britain has no official tactical weapons, though its strategic warheads have a dial-a-yield function that allows them to be programmed to explode in the tactical range, and France has 60 tactical-range cruise missiles, though these are tasked with protecting France itself against attack.

Will Putin use nukes?

However much nuclear weapons are feared, left to themselves they are just so many piles of radioactive clockwork. The real danger is the people who are in charge of the nuclear arsenals and, like all people, they are motivated by rational and irrational factors as well as outside forces.

In the case of Vladimir Putin, the US, NATO, and Ukraine are essentially playing a combination of chess and poker with someone who seems not entirely rational yet is at the focus of some complicated variables.

On a personal level, Putin has a definite taste for making colorful threats and likes to push the envelope. He also has no reservations against taking human life, as can be seen in both the conduct of Russian forces in Ukraine as well as Putin's use of assassination as a means of dealing with dissent. That Putin has survived for decades as the leader of Russia shows he has a strong streak of pragmatism where he weighs the odds before taking action.

Complicating this is Putin's frightening miscalculation in Ukraine that turned a war that should have ended in a week to one that could stretch on for years. The annexation of the Russian-ethnic provinces was supposed to provide Putin with a way of declaring victory and to justify his threats to go nuclear, but losing territory to Ukraine just as he was declaring the annexation of provinces that he doesn't even completely control, with the attendant psychological impact, made his fallback position just another threat to his rule.

Then there's the weather. Russia has lost more soldiers and equipment than it can afford and the sanctions make it difficult to replace them. He now faces fighting into the freezing Ukrainian winter. The Ukrainians are also facing personnel shortages and winter hardships, but they have the advantage of Western weapons and intelligence assistance.

This suggests that Putin could become desperate enough to order a tactical nuclear strike. On the other hand, he might prefer to keep the nuclear option unplayed as long as he can.

"It’s his style, if you will – he likes to rattle this sword and be very dramatic, but of course, the generic term, 'all means at our disposal,' could also mean many other things." says Hans Kristensen ,a nuclear arms expert at the Federation of American Scientists. "It remains to be seen. I think the key here is that obviously he’s trying to create a new condition, in Russian declaratory nuclear policy, where just someone upsetting the integrity of Russian territory somehow, potentially, is a recipient of a nuclear attack. And that goes beyond anything that is in the current declaratory policy. That certainly requires much more significant steps here. Obviously he’s trying to create a situation where there’s additional coercion – pressure – on Ukraine and the West to stop fighting and seek some kind of negotiated settlement here.

"I think one could read it to sort of say this is what Putin does. This is his chest-thumping style – he likes to use big words to scare other people. But whether it’s reflected in the actual planning they’re doing is another matter and I think that’ll take some time actually before we see that. But there are a number of steps they would have to take before they could use a tactical nuclear weapon in the Ukraine conflict. It’s not like he has a red button on his desk and he could just press that when he feels like it."

If tactical nukes are used, how would it happen?

Even though Putin is an autocrat, he would probably have to consult with at least two other people, one of whom is Russian Chief of the General Staff, Army-General Valery Gerasimov, and the other the Minister of Defense Sergei Kuzhugetovich Shoigu, to receive unanimous agreement before ordering a tactical strike. This might not be very easy to get if there isn't a direct threat to Russia itself and Putin doesn't dare give an order he knows won't be obeyed.

If the Go code is given, the strike won't be a surprise if NATO does its job properly. A tactical strike will mean a lot of communications chatter as orders are sent, queries are sent back, confirmations are given, and preparations are made to move the necessary nuclear weapons, special troops, and gear to the Ukrainian border. These will also be obvious to the ever-present satellites and spy planes, as well as human agents, that are monitoring the region.

Possible targets

If a tactical nuclear weapon is launched, what would be the target? Before discussing this, it's important to emphasize again that we're not talking about an end-of-the-world full-scale nuclear attack on the West or a single missile against Europe or the United States. Either scenario would result in the annihilation of Russia by the US, Britain, and France – any of which have enough nuclear firepower to destroy Russia as a functioning society.

Worse for Putin, a single missile might not get through Western anti-missile defenses and a massed attack might end up as an embarrassing damp squib given the poor condition of the rest of the Russian forces. Putin wouldn't want to launch 300 missiles only to find that two-thirds malfunction on the night and a large fraction of those that do take flight go off target.

That being said, the question remains as to what the target would be. Such a strike would certainly be launched with some purpose in mind. The most likely is to "Copenhagen" NATO and the United States in particular. "Copenhagen" refers to the first Battle of Copenhagen in 1801 when the Royal Navy sailed into Copenhagen Harbor and blasted the Danish fleet at anchor to warn Denmark from making an alliance with Napoleon against Britain.

This worked, but when Japan tried the same tactic at Pearl Harbor in 1941, it managed to destroy the US Seventh Fleet and left the Pacific and the entire US west coast defenseless, but the effect was precisely the opposite, with the Americans reacting by immediately declaring war.

In other words, if Putin tried an attack aimed at frightening NATO directly, it would be a very bad gamble.

The more perplexing problem is that Ukraine isn't suited to a tactical nuclear attack. It doesn't have concentrated battalions, massed armored columns, huge command and control centers, or any other important targets that would justify such an attack. In fact, it may seem paradoxical, but a tactical nuclear attack might turn out to be less effective than a conventional one, by producing loud bangs with little damage to show for them.

As to an attack on a population center, aside from being a moral atrocity, it would very likely stiffen resolve against Russia. A similar argument goes against a demonstration strike at sea or in some deserted area. The world knows all too well that Russia has nuclear weapons. The question is whether Putin has the will to use them. An attack in the middle of nowhere would suggest that he doesn't.

Effects and fallout

The effects of a tactical nuclear strike would be much more limited than a strategic one. If a 20-kiloton warhead is used in an airburst for greatest effect, it would produce a fireball 650 ft (200 m) in diameter and would have a blast radius of 0.8 miles (1.27 km). The direct radiation burst would stretch to 0.9 miles (1.41 km) and the severe heat flash would extend to 1.4 miles (2.27 km, though some tactical nukes are designed to either produce a large blast with little radiation or a small blast with heavy radiation.

As to fallout, there would be some, but an airburst wouldn't throw much dust into the air and the maximum distance the fatal dosage would travel would be about 2.9 miles (4.7 km). Meanwhile, low-level fallout would travel as far as 66 miles (107 km). Beyond that, there would only be detectable traces. It's a plume that, at its heart, would be a real hazard for a few weeks in the vicinity of the wind-borne plume in Ukraine, but there wouldn't be a need for people in New York or Tokyo to take shelter, nor would the affected areas become blighted wastelands where no one ever dares set foot again.

However, fallout might mean that a strike isn't possible unless Putin is willing to simply abandon the affected area of Ukraine. With an army of hastily fielded mercenaries, reservists, and raw recruits with inadequate shelter and equipment, he won't have a force trained to operate in a nuclear environment and would have to retreat

Possible outcomes

The biggest question isn't whether Putin will use a nuclear weapon. It's how to prevent this and what happens next if he does.

One way to deter an attack would be to adopt some of the strategies used against the USSR during the Cold War. NATO could move dual-capable aircraft that can carry both conventional and nuclear payloads to front-line nations, or the US could deploy strategic bombers like the B-52 Stratofortress to Britain or Italy on exercise. It might also be possible to deploy nuclear-capable NATO warships to the Norwegian Sea, the Baltic, and the Black Sea.

If deterrence fails and Putin does launch a nuke into Ukraine, how to respond becomes a very tricky question because NATO is not officially involved in the fighting and Ukraine is not a NATO member state. Balanced with this would be the moral outrage, fear, and panic that would not only grip the people of the world, but also their leadership who would be pressed to "do something" without being sure what that "something" would be.

It might be that the Western response would be restrained – amounting to little more than increased sanctions, more military aid to Ukraine, and cyber warfare attacks against Russian interests. It might also be something as rash as the recent suggestion of the US Navy sinking Russia's Black Sea Fleet or even a tit-for-tat firing of a tactical nuclear weapon by the US at Russian forces in occupied Ukrainian territory.

In between these extremes, NATO might use its technical superiority to wage a gradually escalating standoff war by firing cruise missiles and other long-range weapons over Ukraine to wipe out Russian aircraft and air defense systems without attacking Russia itself.

Whatever the course of action, the absolute top priority would be to prevent the proxy war between the US and Russia from turning into an all-out nuclear exchange. That introduces a whole new set of variables aside from the psychology of Vladimir Putin. Western leaders will have to thread a very tricky path while performing a complex balancing act.

On the one hand, it will be necessary to deter Russia without pushing it into a state of desperation. It also means punishing Putin while keeping in mind that deposing him might only see him replaced with someone far worse. Above all, it means deciding clearly and decisively what the endgame will be in Ukraine and finding some way to navigate this without the launch of more nuclear warheads. Since that could mean bringing about a ceasefire followed by years of negotiations to find a deal that both sides are willing to stomach, that could be a very long balancing act.

Additionally, if a tactical nuclear warhead is launched by Russia to get its way, it will fundamentally change international policy. For over 75 years the use of nuclear weapons has been a hard taboo. If Ukraine leads to even the smallest nuclear bomb being detonated, whether Putin is then punished or deposed or not, it will set a precedent that the world may not be able to come back from.

The Ukraine situation is one that hasn't been seen in over a generation. It's not only having a direct impact around the world already, but if things escalate and those in charge make the wrong decisions, it could be the first time since the 1980s that the world faces the real threat of nuclear war between major world powers.

That's scary.