July 16, 1945 – The Trinity test in New Mexico produces the world’s first nuclear explosion, establishing the baseline for all subsequent testing records and the current eight‑year‑plus hiatus [1].

1996 – China, the United States and Russia sign the Comprehensive Nuclear‑Test‑Ban Treaty but never ratify it, leaving the nuclear‑testing moratorium voluntary and vulnerable [2].

1998 – 2006 – The previous longest testing gap runs from Pakistan’s last test in 1998 to North Korea’s first test in 2006, a benchmark the present hiatus now surpasses [1].

September 3, 2017 – North Korea conducts its most recent nuclear test, the last known nuclear explosion worldwide before the current lull [1].

June 22, 2020 – A magnitude‑2.75 seismic event recorded by a Kazakhstan IMS station 720 km from Lop Nur matches the waveform of a nuclear blast; Assistant Secretary of State Christopher Yeaw says it is “entirely not consistent with an earthquake,” suggesting a covert Chinese test [2][5].

2023 – Russia revokes its ratification of the CTBT, arguing the treaty is imbalanced with the United States, thereby weakening the global testing‑ban regime [4].

October 31, 2025 – President Donald Trump posts on Truth Social that the Department of War will begin nuclear weapons testing “immediately,” citing rival programs as justification and signaling a shift toward active testing [4].

November 10, 2025 – At a Vienna CTBT meeting, U.S. Chargé d’Affaires Howard Solomon declares the United States will resume nuclear testing “on an equal basis” with other powers, arguing low‑yield “supercritical” tests evade detection and that Russia and China have violated the moratorium [3].

December 2, 2025 – Russian President Vladimir Putin tells the UN Security Council that any U.S. or CTBT‑signatory nuclear test will trigger reciprocal Russian testing, reinforcing a tit‑for‑tat stance amid rising tensions [4].

December 18, 2025 – Solomon reiterates the U.S. testing rationale, citing alleged Russian and Chinese activities, Russia’s large non‑strategic warhead stockpile, and the imminent expiration of New START on February 5, 2026, as reasons to abandon the testing moratorium [3].

January 15, 2026 – The world reaches an eight‑year, four‑month, and 11‑day nuclear‑test hiatus—the longest since the 1945 Trinity test—highlighting a record‑setting period of no nuclear explosions worldwide [1].

February 5, 2026 – The New START treaty between the United States and Russia expires, removing the last major bilateral limit on strategic nuclear arsenals and raising the risk of rapid warhead deployment [3].

February 17, 2026 – At a Hudson Institute event, Christopher Yeaw repeats that the 2020 Lop Nur seismic signal matches a nuclear blast, arguing the United States may need to test “on an equal basis” to counter China’s “hundreds‑of‑tons” yield capability [5].

February 18, 2026 – A senior U.S. official publicly details the alleged 2020 Chinese underground test, describing China’s use of “decoupling” to mask a yield of several hundred tons and warning that the United States “cannot afford to forgo testing” or face an “intolerable disadvantage” against peer rivals [2].

February 18, 2026 – The United States pushes for a new three‑way arms‑control pact with China and Russia after New START’s expiry, seeking to replace the lapsed treaty and to constrain future testing while China and Russia deny any 2020 test [5].