The New START treaty, the last remaining major arms control agreement between the United States and ⁤Russia, has expired ⁢as of February 5, 2026, raising concerns about ⁤a renewed ⁢nuclear arms race.The treaty, which limited the number ‍of strategic nuclear warheads each ⁤country⁣ could deploy, was extended in 2021 for five years, but further extension talks stalled amid heightened geopolitical tensions.