The second was the first-ever nuclear test explosion, known as Trinity, conducted in New Mexico on 16 July 1945. In the ensuing decades, nuclear weapons testing escalated at an alarming rate. This day is a solemn reminder that nuclear testing must become a relic of the past. A return to nuclear testing would almost certainly spark a dangerous arms race, one that undermines the purposes for which the UN was founded. If no nuclear test is conducted by 14 January 2026, the world will set a record for the longest period without a nuclear test since 1945.