The threat of nuclear war is widely recognized to be at its highest level since the Cold War. Two ongoing major conflicts involving nuclear-armed states, Russia and Israel, have both included threats to use nuclear weapons, and nuclear tensions are roiling the Korean peninsula. Even a limited nuclear conflict would have much more devastating global consequences than previously imagined, according to recent research.

But a significant group of countries are leading efforts to avoid this catastrophe—the states parties to the U.N. nuclear ban treaty. At their regular meetings—the most recent just wrapped up at the United Nations in New York—they advance the treaty’s implementation, including efforts to get every country to join, and to take forward an unprecedented structure of international assistance for victims of the use and testing of nuclear weapons.

The only way to ensure nuclear weapons are never used again is to take them out of arsenals and eliminate them. The international legal route to do this is through the TPNW.

The Treaty on the Prohibition of Nuclear Weapons (TPNW) was adopted by 122 countries in 2017, and came into force in 2021. So far, 97 states, almost half of all countries, have committed to its comprehensive ban on nuclear weapons, as well as their use or threat of use. Many countries that have not yet signed the treaty, including some NATO members and allies of the United States that endorse the use of nuclear weapons, join their meetings as observers.

At the first meeting last year in Austria, TPNW states agreed to the Vienna Action Plan—the first consensus treaty-based plan on nuclear disarmament adopted in over a decade. In the wake of Russia’s invasion of Ukraine, the meeting also condemned unequivocally “any and all nuclear threats, whether they be explicit or implicit and irrespective of the circumstances.” That language has since been echoed by the G20 and individual leaders, including President Xi Jinping, Chancellor Olaf Scholz, and NATO Secretary General Jens Stoltenberg. Nuclear experts assess that these declarations had an impact, causing Russia to stop making such overt nuclear threats.

This year TPNW states called out the doctrine of nuclear deterrence adhered to by the nuclear-armed states and their allies as a threat to human security and an obstacle to nuclear disarmament. The first time a multilateral treaty has taken such a position on deterrence—an unproven theory on which the future of humanity is being gambled based as it is on the implicit threat to use nuclear weapons.

TPNW members know that what has prevented nuclear war is sheer luck, rather than deterrence. Among the close calls that we know of, it was good fortune that individuals who were prepared to defy peer pressure and military protocols happened to be in the right place at the right time. People like Vasily Arkhipov, the Soviet naval officer who prevented a nuclear torpedo being fired during the Cuban missile crisis, and air force officer, Stanislav Petrov, who in 1983, decided on his own accord that the computer telling him the U.S. had launched a nuclear missile strike was malfunctioning and did not pass it up the line.

The TPNW is a young treaty so its members do not just meet to review their implementation of it, they also agree upon ways to strengthen it, including persuading other states to join it. At last week’s meeting, Indonesia announced that its parliament recently approved ratification of the treaty, and several other countries, including Brazil, announced their intent to ratify soon.

Thirty years on from the end of the Cold War, the nuclear-armed states have embarked on a new nuclear arms race, modernizing, and in some cases, expanding their arsenals, which threatens us all.

The only way to ensure nuclear weapons are never used again is to take them out of arsenals and eliminate them. The international legal route to do this is through the TPNW.

Despite sceptics saying nuclear-armed states will not eliminate their nuclear weapons, it has happened before so it can happen again. South Africa got rid of its nuclear arms and is now one of the leading TPNW countries. Other states, including Brazil, Sweden, and Switzerland, had programs to develop nuclear weapons that they decided would not bring them security and abandoned them.

“A nuclear war cannot be won and must never be fought” is not the slogan of anti-nuclear campaigners, these words were spoken by former President Ronald Reagan and Soviet General Secretary Mikhail Gorbachev in 1985, and repeated by the five original nuclear weapons states—the permanent members of the U.N. Security Council—just last year, as well as the G7 this year.

The statement recognizes the existential threat nuclear weapons pose to people and the planet. The rational conclusion to be drawn from it is that it makes no sense to keep nuclear weapons, so all countries need to join the existing members of the TPNW in choosing not to.