Although the world faces deep political divisions, we all face the same common existential risks, threats from which none of us are safe until we are all safe. Nuclear weapons, climate change, and, under some scenarios, disruptive technologies pose existential threats to all humanity, which means, now more than ever, multilateral cooperation to tackle their common challenges is essential.

As the Group of Seven leaders prepare to meet in Hiroshima this week, they are doing so in a world that again faces the threat of nuclear weapon use. Atomic scientists, "largely but not exclusively because of the mounting dangers of the war in Ukraine," have set the Doomsday Clock closer to midnight than ever before. The world is closer to nuclear use than at any time since the 1980s. Ukraine's representative has urged the G-7 leaders to condemn any threat to use nuclear weapons.

In a world of multiple complex problems, international diplomacy and cooperation, particularly about national security, has to be based on the ability and willingness to tackle these common existential challenges, whatever the global geopolitical circumstances. In particular, this skill is essential for nuclear arms control. Even in the darkest hours of the Cold War, the Soviet Union and the United States were both able and willing to discuss and agree on measures to reduce the risks of nuclear Armageddon. They had learned that if you try to solve all the problems at once, you are likely to solve none of them.

That readiness to put aside broader disagreements in the interest of addressing existential common risks is being challenged while Russia's war against Ukraine is waged. The bilateral arms-control architecture between Russia and the United States was already eroding and that negative trend has accelerated. U.S.-Russia strategic stability talks are in limbo and the New START treaty, which has played an indispensable role in ensuring reciprocal security, is now in peril. The clock is ticking: New START will expire in less than three years. As it is now the only nuclear arms control agreement between the United States and Russia, the two largest nuclear-armed countries, the treaty's collapse or expiry without a replacement would likely trigger a destabilizing nuclear arms race. With the U.S.-Russia agreements wearing thin, there is little or no possibility of an expanded arms control architecture that includes the United Kingdom, France and China, whose own nuclear arsenal is growing at a pace.

Cooperation and agreement is possible. In January last year, the five leaders of the nuclear weapon states made a rare joint statement saying that a nuclear war can never be won and must never be fought -- a repeat of the powerful message that U.S. and Soviet Presidents Ronald Reagan and Mikhail Gorbachev agreed upon during the Cold War. The five leaders were able to speak with one voice, declaring the reduction of strategic risks and the avoidance of war between nuclear-weapon states to be their foremost responsibilities.

Further, in their November 2022 meeting in Indonesia, nine months after Russia's invasion of Ukraine, Group of 20 leaders including from the nuclear weapon possessors: the United States, Russia, China, France, the United Kingdom and India agreed that the use or threat of use of nuclear weapons is inadmissible.

The world needs more nuclear arms control, not less, and it needs states to fulfill their legally binding obligations on nuclear non-proliferation and disarmament.

As evidence of this, over 250 security policy leaders from 50 countries are joining us today to call on the leaders of the nuclear weapon states to ensure that nuclear arms control will not be made yet another victim of great-power competition. We are a diverse group, including former heads of state and ministers to the new generation of security experts, with very different views on the geopolitics. But on this point we all come together: responsible leaders must act on the overriding common interest in safeguarding the world from the catastrophe of any nuclear war.

Geopolitical divisions may make this more complicated but, without a doubt, make it more necessary. The good news is there are significant and feasible steps that the five permanent members of the United Nations Security Council, or P5, nuclear weapons states can take now. In particular, the United States and Russia should confirm that they will continue to abide by the New START limits on deployed nuclear forces; resume the work of their bilateral consultative commission that is tasked with implementing the treaty; and commit to pursuing good faith negotiations on a successor framework for New START before its expiration in 2026.

It is not just up to the United States and Russia. All nuclear weapons states should take steps to begin strategic stability talks at a variety of levels and to resume strategic risk reduction talks, particularly in the so-called P5 format. More broadly, all states that have not yet ratified the Comprehensive Nuclear Test Ban Treaty should reaffirm their commitments not to test nuclear weapons and also to make concerted efforts towards entry into force of that treaty.

The P5 individually, bilaterally and collectively therefore have to recapture the spirit that enabled them to work together through much of the Cold War. American and Russian leaders learned during that time that arms control is not a favor to the other side but a precondition for survival in the nuclear age. The time to put that hard-learned lesson into practice is now.

Combined photo shows Des Browne (L) (Getty/Kyodo) and Marty Natalegawa (supplied)(Kyodo)


(Des Browne is former U.K. defence secretary, and current chair, European Leadership Network, and Marty Natalegawa is former foreign minister of Indonesia, and current chair, Asia-Pacific Leadership Network.)