In February 2026, the last remaining U.S.–Russia nuclear arms control agreement, New START, will expire. For more than a decade, this treaty has limited the world’s two largest nuclear arsenals and provided valuable transparency, helping to prevent dangerous escalation.
If New START lapses without a replacement, there will be no legally binding limits on nuclear weapons production by the U.S. and Russia for the first time in more than 50 years. Both nations could quickly expand their deployed arsenals, fueling an arms race that puts the entire world at risk.
A new nuclear arms race would put the entire world at risk.
That is why the principle first affirmed by President Ronald Reagan and Soviet leader Mikhail Gorbachev during the Cold War, “a nuclear war cannot be won and must never be fought,” should guide what comes next.
What a Follow-On Agreement Should Include
If the leaders of the United States and Russia are serious about preventing nuclear war, they should ensure that some form of successor treaty or agreement is implemented following New START’s expiration. This agreement must, at a minimum, maintain existing limits on the U.S and Russian nuclear arsenals.
There are also additional steps both countries should pursue to enhance global stability. These include:
- Deeper reductions in deployed warheads, reducing from the current limit of 1,550 deployed strategic weapons to 1,000 each. This would showcase both countries commitment to the Nuclear Nonproliferation Treaty (NPT), reiterating the urgent need to move closer to nuclear disarmament.
- Freezing and eventually reducing tactical nuclear weapons. These weapons are designed for battlefield use. Their continued production dangerously lowers the threshold for nuclear conflict and increases the risk of nuclear war.
- Managing missile defense and intermediate-range missiles responsibly. In theory, missile defenses are designed to shoot down incoming nuclear missiles. In practice, neither side believes the other is building them only for “defense.” Agreeing on limits or rules for these systems could ease tensions.
- Preserving the global moratorium on nuclear testing. A return to nuclear testing by either country would destroy established norms and further increase tensions.
- Embedding risk-reduction measures like launch notifications and crisis hotlines. These safeguards are crucial to prevent accidents or misunderstandings from spiraling into disaster.
What Can be Done Right Now
Even before negotiations conclude, there are several important and immediate steps the U.S. and Russia could take to honor the Reagan-Gorbachev principle. President Donald Trump and President Vladimir Putin should:
- Jointly reaffirm that nuclear war cannot be won and must never be fought.
- Agree to stay within New START limits voluntarily, preventing a destabilizing buildup after the treaty’s expiration.
- Return to regular bilateral strategic stability talks focused on managing nuclear risks.
Moving Forward
In this critical moment, the jointly held belief by both nations that nuclear war must never be fought needs to be more than a slogan. Instead, it must serve as a roadmap for action.
Negotiations should begin now, and both sides must carry this principle forward into a new arms control agreement. The alternative of unconstrained nuclear competition risks moving both countries away from this simple but vital truth, and toward a more dangerous world for all of us.
