Under Secretary of Energy for Nuclear Security

Under Secretary of Energy for Nuclear Security
S5
Seal of the U. S. Department of Energy
Incumbent Teresa Robbins [1] Acting   since January 20, 2025
United States Department of Energy
Style	Mr./Ms. Under Secretary
Member of	U. S. Department of Energy
Reports to	U. S. Deputy Secretary of Energy
Seat	Washington, D.C., United States
Appointer	The President with Senate advice and consent
Term length	Appointed
Formation	2000
First holder	John A. Gordon
Website	www.energy.gov

The Under Secretary for Nuclear Security, in the United States Department of Energy, is the Administrator for the National Nuclear Security Administration. The National Nuclear Security Administration's responsibilities include designing, producing, and maintaining safe, secure and reliable nuclear weapons for the U.S. military, providing safe, militarily effective naval nuclear propulsion plants, and promoting international nuclear safety and nonproliferation.

The Under Secretary for Nuclear Security is appointed by the president and confirmed by the Senate. The Under Secretary is required to have extensive background in national security, organizational management, and appropriate technical fields. ^[2] The Under Secretary is also a member of the Nuclear Weapons Council, and is the chair of the Council when a majority votes that the issue at hand is the primary concern of the Department of Energy. ^[3] The Under Secretary is paid at level III of the Executive Schedule.

Officeholders

Under Secretary of Energy for Nuclear Security
Administrator of the National Nuclear Security Administration

No.	Portrait	Name	Tenure	Notes	President(s) served under
1		John A. Gordon	June 28, 2000–June 27, 2002	[4] [5] [6]	Bill Clinton
					George W. Bush
2		Linton Brooks	May 16, 2003–January 2006	[7] [8]
3		Tom D'Agostino	August 30, 2007–January 18, 2013	[9] [10]
					Barack Obama
–		Neile L. Miller	January 19, 2013–March 15, 2014
–		Bruce Held	March 16, 2014–April 16, 2014	[11]
4		Frank Klotz	April 17, 2014–January 20, 2018	[12] [13] [14]
					Donald Trump
5		Lisa Gordon-Hagerty	February 22, 2018–November 6, 2020	[15] [16] [17]
–		William Bookless (acting)	November 6, 2020–January 20, 2021	[16] [18] [19]
–		Charles P. Verdon (acting)	January 20, 2021–July 26, 2021	[20]	Joe Biden
6		Jill Hruby	July 26, 2021–January 20, 2025	[21] [22]
–		Teresa Robbins	January 20, 2025–present	[23]	Donald Trump

References

1. https://www.energy.gov/nnsa/person/teresa-robbins
2. "US CODE: Title 42,7132. Principal officers" . Retrieved September 24, 2007.
3. "US CODE: Title 10,179. Nuclear Weapons Council" . Retrieved September 24, 2007.
4. "NNSA Established | National Nuclear Security Administration". NNSA. Archived from the original on 2014-04-13. Retrieved 12 April 2014.
5. "#OnThisDay in 2000". NNSA. June 28, 2024 – via Instagram.
6. "Timeline of Events: 2002". DOE.
7. "Amb. Linton Brooks Sworn in as NNSA Administrator | National Nuclear Security Administration". NNNSA. Archived from the original on 2017-06-03. Retrieved 12 April 2014.
8. "NNSA Administrator to Depart | Department of Energy". CMS. 2007-01-04. Archived from the original on 2016-03-04. Retrieved 12 April 2014.
9. "Thomas P. D'Agostino | Department of Energy". energy.gov. Archived from the original on 2012-06-07. Retrieved 26 Feb 2018.
10. "Thomas D'Agostino, NNSA Head, Stepping Down". Huffingtonpost.com. 21 December 2012. Retrieved 12 April 2014.
11. {cite web |url=https://www.exchangemonitor.com/held-takes-over-as-acting-nnsa-administrator/ |title=Held takes over as acting NNSA administrator |date=March 17, 2014 |publisher=ExchangeMonitor}}
12. "Lieutenant General Frank G. Klotz, USAF (Ret), Confirmed as Energy Department Under Secretary for Nuclear Security and Administrator for the National Nuclear Security Administration". National Nuclear Security Administration. Archived from the original on November 8, 2014. Retrieved April 11, 2014.
13. "DOE Bids Farewell to NNSA's Klotz". U.S. Department of Energy. Retrieved January 30, 2018.
14. Holmes, Sue Major (May 16, 2014). "New NNSA Administrator Frank Klotz visits Sandia". SNL.
15. "Lisa Gordon-Hagerty Confirmed as Energy Department Under Secretary for Nuclear Security and Administrator for the National Nuclear Security Administration". National Nuclear Security Administration. November 6, 2020. Retrieved November 6, 2020.
16. "Lisa E. Gordon-Hagerty Resigns as NNSA Administrator - Dr. William Bookless Now Serving as Acting NNSA Administrator". National Nuclear Security Administration. November 6, 2020. Retrieved November 6, 2020.
17. "Lisa E. Gordon-Hagerty Sworn in as the Department of Energy's Under Secretary for Nuclear Security and Administrator of the National Nuclear Security Administration". DOE. February 22, 2018.
18. Mehta, Aaron (November 6, 2020). "Head of nuclear weapons agency unexpectedly resigns". Defense News. Retrieved November 6, 2020.
19. "Acting NNSA administrator to step down on Inauguration Day". American Nuclear Society. January 14, 2021.
20. "Dr. Charles Verdon". DOE. Archived from the original on 2021-08-10.
21. "Jill Hruby sworn in as Department of Energy's Under Secretary for Nuclear Security and Administrator of the National Nuclear Security Administration". DOE. July 26, 2021.
22. Winkie, Davis (February 14, 2025). "US nuclear weapons agency hit by layoffs after DOGE exemption denied". USA Today .
23. Marsh, Rene; Nilsen, Ella (February 14, 2025). "Trump officials fired nuclear staff not realizing they oversee the country's weapons stockpile, sources say". CNN .