Nuclear Issues

Russia's 2022 invasion of Ukraine illuminated the long profound shadow of nuclear weapons over international security. Russia's nuclear threats have rightfully garnered significant attention because of the unfathomable lethality of nuclear weapons. However, the use of such weapons in Ukraine is only one way—albeit the gravest— that Russia could challenge the global nuclear order. Russia's influence extends deep into the very fabric of this order—a system to which it is inextricably bound by Moscow's position in cornerstone institutions such as the Nuclear Non-Proliferation Treaty (NPT) and the International Atomic Energy Agency (IAEA). From withdrawing from key treaties to stymieing resolutions critical of misconduct, Moscow has demonstrated its ability to challenge the legitimacy, relevance, and interpretations of numerous standards and principles espoused by the West.

Kari A. Bingen and Heather W. Williams write that if Russia plans to deploy nuclear weapons in space to target satellites, the threat is definitely serious—and the U.S. should act fast.

At a moment when arms control is deeply troubled and may be dying, two eminent scholars, Marc Trachtenberg and the late Robert Jervis, have taken a fresh look at the beginnings of strategic arms control fifty years after the signing in Moscow of the SALT I agreements in May of 1972. They do so from different vantage points, writes Steven E. Miller.

This year's G7 summit in Hiroshima sees nuclear disarmament and non-proliferation sitting high on the agenda, amid rising tensions between the nuclear states and an increasingly divided international order.  Six contributors offer their analyses, including the Belfer Center's Mayumi Fukushima.

Earlier this month, South Korean President Yoon Suk-yeol set off alarms. In an off-the-cuff remark, he warned that Seoul might need to develop nuclear weapons—or demand redeployment of U.S. nuclear arms to the Korean Peninsula—to counter North Korean nuclear threats. In doing so, Yoon spotlighted a popular view once reserved for hawkish commentators, defense intellectuals, and former military officials. Keeping nuclear weapons out of South Korea will ultimately be a U.S. responsibility that requires addressing both the deteriorating security environment and the domestic drivers underlying Yoon’s statement.

As diplomats, activists, and researchers converged on Vienna in June for the first meeting of states-parties to the Treaty on the Prohibition of Nuclear Weapons (TPNW), recent tragic world events highlighted how critical it was to convene this multilateral forum on nuclear disarmament.

Since February, Russia’s war against Ukraine has epitomized the grave dangers of a world where nine states possess approximately 12,700 nuclear weapons.¹ That Russia could invade a sovereign state and indiscriminately target its civilian population, while using nuclear threats to deter NATO from intervening, has stunned the world. It offers a stark reminder that possessing nuclear arms can enable abhorrent violations of international law

Although Russia has relied exclusively on conventional weapons for its invasion of Ukraine, behind the scenes lurks Moscow’s massive nuclear arsenal. Hours before Russian forces crossed into Ukraine, Russian President Vladimir Putin reminded the world that his country was “one of the most powerful nuclear states” and that anyone who interfered with his war in Ukraine or threatened Russia directly would face “consequences that you have never faced in your history.” Three days later, as global outrage grew, Putin ordered Russia’s nuclear forces to a higher level of readiness. Even without these explicit threats, Russia’s nuclear deterrent would have prevented Western countries from intervening in Ukraine. Beyond supplying Kyiv with anti-armor and light air defense weapons, they will not come to Ukraine’s defense for fear of nuclear escalation, as U.S. President Joe Biden and other NATO leaders have made abundantly clear. Now that Putin’s attempts to seize Kyiv have been thwarted, there is a risk he will use tactical nuclear weapons to bring Ukraine to its knees. And while this scenario remains unlikely, neither Ukraine nor NATO can do anything to prevent it from happening.

This is a particularly bitter pill to swallow for Ukraine, since it was once home to the world’s third-largest cache of nuclear weapons. After the collapse of the Soviet Union, Ukraine inherited a significant slice of the Kremlin’s nuclear arsenal. But in 1994, the newly independent country decided to surrender that arsenal in exchange for assurances from Russia, the United Kingdom, and the United States that its sovereignty and territorial integrity would be respected. The agreement, known as the Budapest Memorandum, is one that many Ukrainians have come to regret—first in the wake of Russia’s 2014 annexation of Crimea and invasion of eastern Ukraine, and now even more so after its all-out assault on the country. If Ukraine had held on to its arsenal, many have argued, Putin would never have dared to invade the country.

Mariana Budjeryn, research associate at Managing the Atom, speaks about the legacy of the 1994 Budapest Memorandum and the remnants of Soviet nuclear weapons in Ukraine.

The hard truth is that the United States now has few good options for containing Iran’s nuclear program. It can persist with the no-deal status quo, allowing Iran to continue inching closer to a bomb while suffering under sanctions. It can pursue a return to the 2015 agreement and then attempt to get Iran to agree to a “longer and stronger” pact, as the Biden team has suggested. It can try for various other deals, either more or less stringent than the 2015 agreement. Or it can attempt to destroy Iran’s nuclear infrastructure with a military strike, possibly setting Tehran’s progress toward a bomb back by a few years but almost certainly provoking retaliation and possibly a sprint toward the nuclear finish line.

While China is building nuclear reactors faster than any other country in the world, major constraints may limit nuclear energy’s ability to grow to the scale of hundreds of gigawatts that would be required for it to play a major part in decarbonizing China’s energy system. This chapter explores the major constraints on, and risks of, large-scale nuclear energy growth in China, and how both new policies and new technologies might address them. It focuses particularly on the two biggest constraints – economics and siting. Substantial government policies to support nuclear power and advanced reactor systems designed to address some of the key constraints are both likely to be needed for nuclear to have a chance of playing a major role in decarbonizing China’s energy system; nuclear energy’s role may be bigger in the second half of this century than in the first half.