This has sort of slipped under the radar.

On 4 February 2026, US and Russia’s nuclear weapons treaty is set to expire. If it does, it will mark the first time since the early 1970s that there will be no legally binding limits on US and Russian strategic nuclear forces without another agreement being under negotiation. This would mark a significant break in more than five decades of bilateral nuclear arms control, and a move away from nuclear restraint, making the world a more dangerous place.