It is a historic moment, and not in a good way — on February 5, the last remaining bilateral treaty between the United States and Russia limiting strategic nuclear arms — New START — will expire, and the path to unconstrained nuclear competition will be unimpeded.
For the first time in more than 50 years, the two countries possessing 90% of the world’s nuclear weapons will have no mutually agreed constraints on their arsenals, and no ongoing dialogue to manage their nuclear relationship and reduce the risk of nuclear war.
It is a moment of increasing peril for the US and the rest of the world, and yet it feels that we are sleepwalking into a deeply dangerous new era without — quite literally — a wake-up call.
I helped negotiate the original START Treaty and New START, which entered into force on February 5, 2010.
That treaty was built on a decades-long series of negotiated bilateral treaties to limit and reduce the US and Russian arsenals from their Cold War era high levels of 30,000 warheads on each side.
New START limited each country to 1,550 deployed warheads and 700 deployed intercontinental ballistic missiles (ICBMs), submarine-launched ballistic missiles (SLBMs), and heavy bombers equipped to carry nuclear armaments. Just as important were the treaty’s extensive requirements for data exchanges and onsite inspections.
Not many Americans realize that up until the COVID-19 pandemic began, American and Russian inspection teams were checking each other’s nuclear weapons-related sites 18 times a year. Even then, both countries continued to exchange more than 1,000 notifications each year to report movements and changes in the deployment status of missiles, bombers, and warheads limited by the treaty.
Regrettably, after the pandemic eased and a resumption of inspections should have been possible, Russia refused to restart them, citing its war in Ukraine, and eventually, both sides ended notifications too. Nonetheless, both continued to abide by the treaty’s numerical limits and indicated they would do so until its expiration on February 5.
By its own terms, the treaty cannot be extended after its maximum duration of 15 years, which will expire this week, though it can be superseded by a new agreement. In September, Vladimir Putin formally proposed that the United States and Russia continue abiding by the Treaty’s central limits for another year. Initially, President Trump told the press he thought that was a good idea; more recently, he has said it would be okay if the treaty lapsed because he would negotiate something better. As far as we know, the US has not yet provided an official response to Russia.
Moreover, there has been no effort to resume US-Russia dialogue on strategic stability and nuclear arms control, and what to do when New START expires. That is what makes this moment so disturbing: the era of mutual nuclear restraint is coming to an end, and neither side is demonstrating any urgency to re-engage on this matter of mutual existential interest. Both are now poised, for the first time in decades, to build up their strategic nuclear arsenals rather than reducing them together.
This is an extremely complex, dangerous, and unprecedented historical moment. In the nuclear sphere alone, there are conflicts involving the big nuclear powers and acute competition between them.
Not only has the arms control architecture between Russia and the West unraveled, but China is now expanding its nuclear arsenal more quickly than imagined even a few years ago. North Korea’s nuclear and missile arsenal has grown unabated, and there is no ongoing diplomacy to address it. Iran’s threshold nuclear program continues to advance, while India and Pakistan fought and may have come close to nuclear blows last year.
The Nuclear Non-Proliferation Treaty (NPT) is under strain, as non-nuclear-weapon states are beyond frustrated that the recognized nuclear powers — China, France, Russia, the UK, and the US (referred to as the P5) — are failing to uphold their treaty obligation to work in good faith toward disarmament.
Proliferation pressures are growing as non-nuclear states see Ukraine and fear attacks by nuclear states, and allies are increasingly uncertain whether they can count on US guarantees for their security. It is a grim sign of the times that Sweden, that most pacific and internationally minded of 20th-century nations, is now discussing nuclear weapons options with the UK and France. Talk of a Nordic nuclear option is growing.
Meanwhile, civil nuclear technology is spreading as more countries seek nuclear energy, but that can also lead to latent military capability. Newer technologies like cyber and AI raise growing risks of unintended or miscalculated use of nuclear weapons as they increasingly interact with nuclear weapons systems.
What seems most dangerous of all in this moment is the complacency of leaders and of the public in their willingness to live with these nuclear risks as if time were on our side. It is not. At some point, especially with global leadership lacking, the element of luck that has helped ensure the nuclear peace over the past 80 years since Hiroshima and Nagasaki will run out.
It is incumbent on leaders of countries with nuclear weapons to manage those arsenals responsibly and to ensure that they are never used. As the two states with by far the largest nuclear arsenals, the United States and Russia bear the responsibility to continue to maintain limits, transparency, and predictability on those arsenals, and ideally to continue the reduction process and address all classes of nuclear systems.
President Trump should agree with Putin that they will continue to abide by New START limits for another year and use that as the foundation for new negotiations. They should agree on broad principles and goals for the next nuclear agreement and direct their interagency expert teams to the negotiating table to start working through the complex details. It will not be a quick process.
It is also essential for the US and China to develop a more mature nuclear dialogue and pursue confidence-building measures and eventually arms control. But a trilateral agreement now seems improbable, given that China’s growing arsenal is still vastly smaller than that of the US and Russia, and with Beijing resisting any idea of negotiations.
In their meetings this year, President Trump should raise the issue with President Xi Jinping and work to prioritize nuclear risk reduction by mandating their military and diplomatic experts to regularize dialogue and get to work on confidence-building measures.
The P5 nuclear dialogue process should also be reinvigorated to demonstrate commitment to the NPT, and to agree on steps and commitments that will facilitate further US-Russian reductions, and lay the foundation for eventual P5 negotiations.
The transatlantic circuits are overloaded, and threats to European sovereignty from the East and now — shockingly — also from the West have shuffled the agenda and priorities for Europeans in unimaginable ways. Nonetheless, what was true during the Cold War remains so now: European security is enhanced when the US and Russia maintain legally binding verifiable limitations on their nuclear forces. This should not be seen as a concession to Russia or as an undeserved reward; it is a legitimate means of threat reduction that should be pursued.
Once there is a cessation of hostilities in Ukraine, a more lasting peace in Europe will require a reimagined security architecture for Europe — one that addresses not only nuclear systems but conventional as well.
But even before that day arrives, if European leaders and publics consider, as I do, that their security depends in part on keeping the nuclear peace, they should be calling on Russia and the United States to continue their decades-long practice of mutually limiting and reducing their nuclear arsenals with verification and predictability.
They should encourage both presidents to continue to abide by New START’s numerical limits and get back to the negotiating table on the next agreement. The US must consult Europe closely on strategic arms control, and Europe must have a seat at the table when it comes to negotiating a new security architecture for the continent.
Lynn Rusten is a CEPA Nonresident Senior Fellow and is an independent national security consultant. She served as the vice president for the Nuclear Threat Initiative’s Global Nuclear Policy Program from 2018 through 2024, where she led efforts to reduce the risk of nuclear weapons use and proliferation. Rusten has held senior positions in the White House, Department of State, and Congress. She served as the senior director for arms control and nonproliferation on the White House National Security Council staff and held key roles at the Department of State. Rusten holds an MS in national security strategy from the National War College, an MA in Russian and East European studies from the University of Michigan, and a BA in government with high honors from Oberlin College.
Europe’s Edge is CEPA’s online journal covering critical topics on the foreign policy docket across Europe and North America. All opinions expressed on Europe’s Edge are those of the author alone and may not represent those of the institutions they represent or the Center for European Policy Analysis. CEPA maintains a strict intellectual independence policy across all its projects and publications.
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