Thomas G. DiNanno

Under Secretary of State for Arms Control and International Security

Appears in 1 story

Office: Under Secretary of State for Arms Control and International Security

Education: Middlebury College, Massachusetts Institute of Technology, University of Pennsylvania

Last updated Nov 2, 2026

Stories

US accuses China of secret nuclear test at Lop Nur

Force in Play

As of May 2026: Active; leading US nuclear diplomacy

No country has acknowledged conducting a nuclear test since 1998. On February 6, 2026, the United States accused China of secretly breaking that taboo by detonating a nuclear device at its Lop Nur test site in June 2020. Beijing masked the explosion using underground caverns that muffle seismic waves.

Updated May 29