What to Know About an Under-the-Radar Defense Agency That Developed Bunker Busters Used in Iran

The Defense Threat Reduction Agency helps develop customized methods to defeat emerging threats from so-called weapons of mass destruction.

A satellite view shows an overview of Fordow underground complex, after the U.S. struck the nuclear facility, near Qom, Iran, on June 22, 2025. Maxar Technologies/Handout via Reuters

The June 21 U.S. stealth bomber strike on Iran, culminating more than 15 years of planning and preparation, has brought new attention to the Defense Threat Reduction Agency (DTRA).

Formally established in October of 1998, DTRA has described itself as a research and development component for the Department of Defense that can trace its origins to the “Manhattan Project” in World War II, which oversaw the development of the first U.S. atomic weapons.