Will more countries want nuclear weapons after the war in Ukraine?

On a certain level, many of today’s most pressing U.S. national security problems are really just variations of one problem: how to manage the risk of armed conflict in a world with nuclear weapons.

The question haunts American foreign policy on multiple fronts. In Ukraine, the key question the U.S. and its allies are facing is how much military support they can provide without risking an all-out NATO-Russia war that could end civilization as we know it. President Joe Biden’s trip to Asia last week was interrupted by multiple missile tests from nuclear-armed North Korea and overshadowed by his vow to defend Taiwan with military force if it were attacked by China, a scenario many analysts have projected could easily go nuclear. Then there are the ongoing talks over the Iran nuclear agreement: Then-President Donald Trump pulled the U.S. out of the deal in 2018, and Biden has pledged to return to it, but negotiations have stalled. That has in turn raised the risks of armed conflict or a nuclear arms race in the Middle East.

Almost eight decades after Hiroshima, only nine countries possess their own nuclear weapons, far fewer than many predicted at the dawn of the nuclear age. (South Africa gave up its arsenal in 1989.) The fact that nuclear weapons have not been used in warfare since 1945 and that so few countries have acquired them is a testament both to how frightening these weapons are, and the robust norms and penalties in place to prevent their spread.

It’s still very difficult to build a nuclear bomb. While the technology itself is older than color television, acquiring the necessary fissile materials is an expensive and tricky process that, if publicly disclosed, exposes a country to international sanctions, isolation or military strike. While it is true that these factors didn’t prevent North Korea from acquiring a nuclear weapon, most countries don’t want to wind up as isolated and poor as North Korea. There’s a reason most of the roughly 30 countries that have pursued a nuclear weapon never got there.

But recent events have raised troubling signs that the norms against nuclear weapons proliferation are breaking down and that more countries may see it in their interest to acquire them. Governments looking at Ukraine and Russia may well conclude that a nuclear arsenal can help a powerful state impose its will on its neighbor. And they may look at North Korea and see how even the most erratic and isolated rogue regime can acquire a degree of international clout by building a nuclear arsenal.

And as these norms break down, the bigger concern is that the norms against the use of nuclear weapons could follow.

“The more states that pursue nuclear weapons, that threaten to pursue nuclear weapons, that threaten to use nuclear weapons, all of that increases nuclear risk, in part because it increases the risk of miscalculation,” Kelsey Davenport, director of nonproliferation policy at the Arms Control Association, told Grid.

Where are these risks most acute? And what can be done to contain them?

Ukraine

On the one hand, if anything demonstrates the dangers of a world with nuclear weapons, it’s the war in Ukraine. And yet, it’s also a demonstration of why countries want to have them. Russia’s nuclear arsenal is one big reason why it has been able to invade a neighboring country (a relatively rare event in today’s world) without facing an international military response.

It also seems far less likely that Russia would have invaded had Ukraine possessed a nuclear arsenal of its own. Compounding the frustration for Ukrainians is the fact that the country did have nuclear weapons on its territory — around 1,900 Soviet warheads at the end of the Cold War in 1991, making it, on paper, the world’s third-largest nuclear power. In 1994, the newly independent nation of Ukraine agreed to give those weapons to Russia in exchange for internationally negotiated security guarantees that turned out to not be so ironclad. While Ukraine never actually had control of the weapons, which were connected to command-and-control systems in Moscow, it’s a powerful narrative nonetheless. As the country’s former defense minister told the New York Times in February, shortly before the invasion, “We gave away the capability for nothing.”

Nicholas Miller, a political scientist at Dartmouth College who studies nuclear proliferation, said the current war and recent history underline the advantages of the nuclear capability. “It’s already well understood that nuclear weapons seem to do a pretty good job at deterring outright invasions,” he told Grid, pointing out that North Korean officials regularly invoke the examples of Iraq and Libya, which abandoned their weapons of mass destruction programs and then found themselves targets of U.S.-led regime change operations. “This just kind of reinforces that.”

None of which suggests a looming global rush to obtain the bomb. Davenport said the more likely possibility is more states engaging in nuclear “hedging”: developing the capabilities to quickly build a bomb without crossing the red line of actually doing so. Countries have done this as an insurance policy in case security guarantees provided by their partners turn out not to be flawed, or weak. Japan and Germany are often cited as examples of this “hedging” strategy.

Another potential casualty of the war in Ukraine is nuclear diplomacy between countries that already have the weapons. Just after Biden took office in January 2021, he and Russian President Vladimir Putin reached a last-minute agreement to extend the New START treaty by five years. The deal, which was signed in 2010 and limits each country to 1,550 deployed nuclear weapons, was set to expire in February 2021. Notably, the U.S. and Russia have continued to provide each other with regular updates about their nuclear forces, as required under the treaty, even amid the carnage and saber-rattling of the war in Ukraine.

But it’s now much harder to imagine any serious progress on arms control diplomacy. The New START treaty will formally expire in 2026, and Ankit Panda, senior fellow in the nuclear policy program at the Carnegie Endowment for International Peace, told Grid “it’s incredibly difficult for me to imagine the U.S. Senate being in any mood to sort of approve an arms control agreement with Russia that isn’t anything but completely in the United States’ asymmetric favor. And that just isn’t how these agreements play out in practice.”

Without progress, the New START deal and any potential future U.S.-Russia arms-reduction agreements will be at risk.

Iran and the Middle East

The negotiations over a revival of the Iran nuclear deal have been on life support for so long, it sometimes seems like they will never actually die. But at the moment, it’s hard to see a path forward toward an agreement. The current sticking point is Iran’s demand that the Biden administration remove the country’s Revolutionary Guard Corps from the U.S. terrorist blacklist, where Trump placed it in 2019.

Biden has reportedly made a final decision not to delist the group, which is accused of repressing dissent within Iran and fomenting violence throughout the Middle East. While the two sides appeared to be on the verge of an agreement as recently as March, talks are now deadlocked, and the other parties to the landmark nuclear pact are getting nervous. “Every day which passes without achieving agreement, the risk to lose everything increases considerably,” one European diplomat told the journalist Laura Rozen. Even the chief U.S. negotiator, Rob Malley, conceded in congressional testimony last week that “the odds of a successful negotiation are lower than the odds of failure.”

The stakes are high. Since the U.S. quit the pact, Iran has been ramping up the enrichment activities that the agreement prohibited. A report from the International Atomic Energy Agency this week reportedly concludes that Iran now likely has enough enriched uranium to allow it to build a weapon and could convert that uranium to weapons-grade material in just a few weeks. Does this mean that failure at the negotiating table will lead inevitably to a nuclear-armed Iran? Not necessarily. Some experts believe Iran, which still denies it has any intention of building a bomb, is also pursuing a hedging strategy, stopping just short of doing so. In this scenario, Iran would avoid the additional sanctions and isolation that would result from actually going nuclear, while preserving the option to do so quickly were conditions to change.

If Iran did actually build a bomb, the risk of a regional arms race would spiral. Crown Prince Mohammed Bin Salman, the de facto ruler of Saudi Arabia, Iran’s regional rival, has explicitly said that “if Iran developed a nuclear bomb, we will follow suit as soon as possible.” U.S. intelligence agencies have reportedly been scrutinizing Saudi Arabia efforts to produce nuclear fuel, allegedly assisted by China; these remain far short of what would be needed to produce a bomb, but some experts believe they represent a way for the kingdom to keep its options open. Recep Tayyip Erdogan, president of Turkey, which hosts a number of U.S. nuclear weapons on its territory, has also talked openly about developing a nuclear deterrent.

For the time being, the only nuclear power in the Middle East is Israel, and it would like to keep it that way. Israel has possessed weapons since the 1960s, though it does not publicly acknowledge that fact. Israel has been linked to an ongoing campaign of sabotage and assassination targeting Iran’s nuclear program, including the killing of the country’s top nuclear scientist with a remote-controlled machine gun last year. Israel has also carried out drills simulating a military strike on Iran’s nuclear program. There’s reason to think this is not an idle threat: In previous decades, Israel has carried out airstrikes on suspected nuclear sites in Syria and Iraq.

This highlights one of the drawbacks of the “hedging” strategy: If a country is close to developing a nuclear deterrent without actually acquiring one, it increases rather than decreases its risk of being attacked.

East Asia

North Korea became the world’s ninth nuclear power in 2006, and as much as the rest of the world may not like it, there’s little chance it will give up its nuclear status as long as the Kim regime is in power. From the North Korean perspective, nuclear weapons represent a powerful hedge against foreign invasion or regime change, and allow the country to exert pressure and extract concessions from the U.S. and its neighbors.

Would those neighbors be better off with nuclear weapons of their own? Most South Koreans think so. About 70 percent support their country developing its own nuclear deterrent, according to recent polls. South Korea had a nuclear weapons program in the 1970s but gave it up under heavy pressure from the U.S. The country also hosted a number of U.S. nukes from 1958 until 1991, and the U.S. continues to provide security guarantees to South Korea, under what is often referred to as the “nuclear umbrella.”

Still, the polls suggest many Koreans would prefer to have their own nuclear program, for the autonomy and prestige it would afford. Notably, many of those who support a nuclear deterrent see China rather than North Korea as the country’s biggest national security threat going forward. (China’s nuclear arsenal is still tiny compared with the U.S. and Russia, but the Pentagon assesses it could quadruple by the end of this decade.)

The politics are starkly different in Japan, the only country where a nuclear bomb has ever been dropped and where public opposition to their use remains high. Nonetheless, Japan has a highly developed nuclear enrichment program and enough materials to produce a bomb in about six months, a state of affairs that has been dubbed its “bomb in the basement.”

Then there is Taiwan, where fears of conflict run high. An increasing number of prominent commentators in both Washington and Taipei are now also calling for Taiwan to develop a nuclear deterrent, rather than rely on security guarantees from Washington, no matter how forcefully Biden might articulate them. The lessons of the war in Ukraine may only reinforce such jitters and increase the calls for a nuclear capability.

U.S. credibility

Ultimately, when it comes to nuclear proliferation, the most important country to watch may be the U.S. Most proliferation scholars argue that countries tend to build nuclear weapons not only when they feel threatened from abroad, but also when they cannot count on security guarantees. And for many countries, the most important such guarantee involves the United States.

This isn’t a new problem. France decided to develop a nuclear deterrent of its own in the 1950s and 1960s over concerns about the reliability of U.S. security guarantees. President Charles de Gaulle famously asked John F. Kennedy if the U.S. would be really be willing to “trade New York for Paris” in the event of a Soviet attack.

The concept of “extended deterrence” — the ability of U.S. military power to deter attacks against its allies — looks less ironclad after the presidency of Trump, who repeatedly questioned the value of alliances with NATO and individual nations including Japan and South Korea. Trump denigrated those countries as freeloaders, suggested they develop nuclear weapons of their own and may well have pushed to withdraw the U.S. from NATO had he won a second term, according to senior officials, including former national security adviser John Bolton.

“For pretty much any country that is a beneficiary of American extended deterrence, the most important national security issue is American domestic politics,“ said Panda, of the Carnegie Endowment. “All their military planning flows from this idea that at the end of the day, American presidents would probably come to their assistance. So, I think this ‘America First’ thinking really does cause a great degree of concern in many of these countries.”

Perhaps the Trump years were an aberration. For one thing, there is now strong (though not universal) bipartisan support for military aid to Ukraine. But it’s worth noting that no existing alliances or prewar pledges of support were enough to deter Putin, and Ukraine had none of the mutual defense guarantees enjoyed by members of NATO or some U.S. allies in East Asia.

In the wake of Russia’s invasion, other countries facing the threat of attack and invasion are likely to seek protection and security guarantees. If the U.S. and other major powers don’t want those guarantees to involve nuclear weapons, they need to show that there are alternative sources of security — and that they actually work. If not, a new race for nuclear weapons may be on the horizon.

Thanks to Lillian Barkley for copy editing this article.