New START nuclear arms treaty expiring 2026: what to know

New START, the last U.S.-Russia nuclear arms treaty, is nearing expiry, ending caps on deployed strategic warheads and delivery systems and halting on-site inspections. Moscow has suspended participation; Washington says Russia is noncompliant. Without renewal or a successor framework, verification lapses, risks of miscalculation grow, and arms racing pressures rise, making 2026 a pivotal moment for global security and stability.