# Assistant Secretary of Defense for Nuclear, Chemical & Biological Defense Programs

The Assistant Secretary of Defense for Nuclear, Chemical & Biological Defense Programs, or ASD(NCB), is the principal adviser to the Secretary of Defense, Deputy Secretary of Defense and the Under Secretary of Defense for Acquisition and Sustainment on policy and plans for nuclear, chemical, and biological defense programs.
The Assistant Secretary of Defense for Nuclear, Chemical & Biological Defense Programs develops policies, advice, and recommendations on nuclear energy, nuclear weapons, and chemical and biological defense, including:
* nuclear weapons;
* chemical, biological, radiological, and nuclear (CBRN) medical and non-medical defense;
* safety and security of chemical and biological agents;
* safety, surety, security, and safe destruction of the current chemical weapon stockpile;
* nuclear, chemical and biological arms control activities and related plans and programs.
The Assistant Secretary of Defense for Nuclear, Chemical & Biological Defense Programs also serves as DoD coordinator and funding administrator for nuclear and conventional physical security equipment research, development, test, and evaluation programs executed by the Military Departments and the Defense Threat Reduction Agency (DTRA).
Before the National Defense Authorization Act for Fiscal Year 2011 on January 7, 2011, the Assistant Secretary of Defense for Nuclear, Chemical & Biological Defense Programs was known as the "Assistant to the Secretary of Defense for Nuclear & Chemical & Biological Defense Programs".
Three Deputy Assistant Secretaries of Defense report to the Assistant Secretary of Defense for Nuclear Chemical & Biological Defense Programs:
* the Deputy Assistant Secretary of Defense for Chemical and Biological Defense (DASD(CBD))
* the Deputy Assistant Secretary for of Defense for Nuclear Matters (DASD(NM))
* the Deputy Assistant Secretary of Defense for Threat Reduction and Arms Control (DASD(TRAC))
In addition, the Director of the Defense Threat Reduction Agency reports directly to the Assistant Secretary of Defense for Nuclear, Chemical & Biological Defense Programs.
The Deputy Assistant Secretary of Defense for Chemical and Biological Defense executes day-to-day management, governance, and resourcing of the Chemical and Biological Defense Program (CDBP) and coordinates with the Executive Agent (EA) for Chemical and Biological Defense (CBD) and other Office of Secretary of Defense components using the procedures and governance framework in DoDI 5160.01.
The Deputy Assistant Secretary of Defense for Chemical and Biological Defense oversees development of Chemical, Biological, Radiological and Nuclear (CBRN) defenses to protect national interests at home and abroad, handling Department of Defense efforts related to:
* science & technology,
* advanced development
* test and evaluation of chemical, biological, radiological and nuclear defenses
* the Chemical and Biological Defense Program Objective Memorandum (POM).
The Deputy Assistant Secretary for Nuclear Matters is primarily the focal point for activities and initiatives related to sustaining a safe, secure, and effective nuclear deterrent and countering threats from nuclear terrorism and nuclear proliferation. This office serves as a primary point of contact for Congress, other agencies, and the public for those programs.
The Deputy Assistant Secretary for Nuclear Matters (DASD(NM)) fulfills the nuclear weapons roles, responsibilities, and functions for the Assistant Secretary of Defense for Nuclear, Chemical and Biological Defense Programs (ASD(NCB)). The Office of the Assistant Secretary of Defense for Nuclear, Chemical, and Biological Defense Programs/Nuclear Matters (OASD(NCB/NM)) is the focal point of the Department of Defense for the U.S. nuclear deterrent. In this capacity, Nuclear Matters is the primary DoD point of contact for Congress, the interagency, and the public and for allies and foreign partners on issues related to the U.S. nuclear stockpile and the integration and alignment of U.S. nuclear weapons and weapons systems. To perform these functions, Nuclear Matters is composed of representatives from all areas of the nuclear community, including the U.S. Navy, the U.S. Air Force, the National Guard Bureau, the United States Nuclear Command and Control Systems Support Staff, the Defense Threat Reduction Agency, the Department of Energy, the National Nuclear Security Agency, Los Alamos National Laboratory, Lawrence Livermore National Laboratory, Sandia National Laboratories, the Kansas City Plant, and the National Security Agency.
The Deputy Assistant Secretary of Defense for Threat Reduction and Arms Control is the principal adviser to the Assistant Secretary for Defense for Nuclear, Chemical & Biological Defense Programs for
* acquisition oversight, implementation, and compliance with nuclear, biological, and chemical treaties;
* cooperative threat reduction; chemical demilitarization programs;
* building global partner capacity to counter weapons of mass destruction.
The OASD(NCB/TRAC) exercises oversight of the Defense Threat Reduction and Agency-executed Cooperative Threat Reduction Program and provides oversight of the Chemical Demilitarization Program.
This office also:
* oversees implementation of and compliance with existing and prospective nuclear, biological, and chemical arms control agreements in accordance with DoDD 2060.1;
* integrates programs to combat proliferation weapons of mass destruction; and
* assists the Deputy Assistant Secretary of Defense for Nuclear, Chemical & Biological Defense Programs as Executive Secretary of the Counterproliferation Program Review Committee (CPRC) and Chair of the Standing Committee of the CPRC.

## History

The Office of the Assistant Secretary of Defense for Nuclear, Chemical & Biological Defense Programs' functions can be traced back to the US Department of Defense's Military Liaison Committee (MLC), formed in the early Cold War to coordinate military requirements with the United States Atomic Energy Commission. The MLC was the channel of communication between the DoD and AEC (and later, the US Energy Research and Development Administration and the US Department of Energy) on all matters relating to military applications of atomic weapons or atomic energy. It addressed matters of policy, programming, and funding of the military application of atomic energy.
In 1951, the Secretary of Defense moved the Military Liaison Committee to the Pentagon. Its chairman became the Deputy to the Secretary of Defense for Atomic Energy Matters. In 1953, this position was renamed the Assistant to the Secretary of Defense for Atomic Energy.
The National Defense Authorization Act for Fiscal Year 1987 (P.L. 99-661, passed in November 1986) abolished the Military Liaison Committee, replacing it with the Nuclear Weapons Council. Just over a year later, the National Defense Authorization Act for Fiscal Years 1988–1989 (P.L. 100-180) created the position of Assistant to the Secretary of Defense (Atomic Energy).
In 1994, the Assistant to the Secretary of Defense (Atomic Energy) was given control over the Defense Nuclear Agency (DNA), which became the Defense Threat Reduction Agency. In February 1996, the National Defense Authorization Act for Fiscal Year 1996 (P.L. 104-106) officially created the office of the Assistant to the Secretary of Defense for Nuclear & Chemical & Biological Defense Programs, or ASTD (NCB) to replace that of the Assistant to the Secretary of Defense (Atomic Energy).
The Clinton administration declined to nominate an Assistant to the Secretary of Defense for Nuclear & Chemical & Biological Defense Programs between 1997 and 2001, having determined (as part of its Defense Reform Initiative) that the position should be eliminated. Congress insisted that the Pentagon maintain the office, arguing it was necessary to ensure appropriate senior-level policy oversight and implementation guidance within the Department of Defense.
In January 2011, President Obama signed the National Defense Authorization Act for FY 2011, renaming the Assistant to the Secretary of Defense for Nuclear & Chemical & Biological Defense Programs the Assistant Secretary of Defense for Nuclear, Chemical & Biological Defense Programs.

## Office Holders

The table below includes both the various titles of this post over time, as well as all the holders of those offices.
Assistants to the Secretary of Defense (Nuclear & Chemical & Biological Defense Programs) :
| Name | Tenure | SecDef(s) Served Under | President(s) Served Under |
| Chairman, Military Liaison Committee ||||
| Lt. Gen. Lewis H. Brereton (USA) | July 17, 1947 – March 30, 1948 | James V. Forrestal | Harry Truman |
| Donald F. Carpenter | April 8, 1948 – September 21, 1948 | James V. Forrestal | Harry Truman |
| William Webster | September 22, 1948 – September 30, 1949 | Louis A. Johnson | Harry Truman |
| Robert LeBaron | October 1, 1949 – April 12, 1953 | Louis A. Johnson George C. Marshall, Jr. Robert A. Lovett Charles E. Wilson | Harry Truman Dwight Eisenhower |
| Chairman, Military Liaison Committee/Assistant to the Secretary of Defense (Atomic Energy) ||||
| Robert LeBaron | April 13, 1953 – August 1, 1954 | Charles E. Wilson | Dwight Eisenhower |
| Maj. Gen. Herbert B. Loper (USAF) | August 9, 1954 – July 14, 1961 | Charles E. Wilson Neil H. McElroy Thomas S. Gates Robert S. McNamara | Dwight Eisenhower John F. Kennedy |
| Dr. Gerald W. Johnson | August 11, 1961 – September 15, 1963 | Robert S. McNamara | John F. Kennedy |
| William J. Howard | January 2, 1964 – June 15, 1966 | Robert S. McNamara | Lyndon Johnson |
| Dr. Carl Walske | October 3, 1966 – April 15, 1973 | Robert S. McNamara Clark M. Clifford Melvin R. Laird Elliot L. Richardson | Lyndon Johnson Richard Nixon |
| Donald R. Cotter | October 16, 1973 – March 17, 1978 | James R. Schlesinger Donald H. Rumsfeld Harold Brown | Richard Nixon Gerald Ford Jimmy Carter |
| Dr. James P. Wade, Jr. | August 8, 1978 – June 14, 1981 June 15, 1981 – June 5, 1982 (Acting) | Harold Brown Caspar W. Weinberger | Jimmy Carter Ronald Reagan |
| Dr. Richard Wagner | June 6, 1982 – April 1, 1986 | Caspar W. Weinberger | Ronald Reagan |
| Dr. Robert B. Barker | October 18, 1986 – November 14, 1986 | Caspar W. Weinberger | Ronald Reagan |
| Assistant to the Secretary of Defense (Atomic Energy) ||||
| Dr. Robert B. Barker | November 14, 1986 – March 3, 1988 (non-statutory) March 4, 1988 – May 29, 1992 (statutory) | Caspar W. Weinberger Frank C. Carlucci III William H. Taft IV (Acting) Richard B. Cheney | Ronald Reagan George H. W. Bush |
| Dr. John Birely (Acting) | May 29, 1992 – May 6, 1993 | Richard B. Cheney Leslie Aspin, Jr. | George H. W. Bush William Clinton |
| Dr. Harold P. Smith, Jr. | June 1, 1993 – March 10, 1996 | William J. Perry | William Clinton |
| Assistant to the Secretary of Defense (Nuclear & Chemical & Biological Defense Programs) ||||
| Dr. Harold P. Smith, Jr. | March 11, 1996 – January 31, 1998 | William J. Perry William S. Cohen | William Clinton |
| Position Vacant | 1998–2001 | William S. Cohen | William Clinton George W. Bush |
| Dr. Dale Klein | November 15, 2001 – June 30, 2006 | Donald H. Rumsfeld | George W. Bush |
| Dr. A. Thomas Hopkins (Acting) | January 31, 2006 – August 2008 | Donald H. Rumsfeld Robert M. Gates | George W. Bush |
| Fred Celec | August 2008 – May 2009 | Robert M. Gates | George W. Bush Barack Obama |
| Andrew C. Weber | May 18, 2009 – January 7, 2011 | Robert M. Gates | Barack Obama |
| Assistant Secretary of Defense (Nuclear, Chemical & Biological Defense Programs) ||||
| Andrew C. Weber | January 7, 2011 – October 1, 2014 | Robert M. Gates Leon Panetta Chuck Hagel | Barack Obama |
| Dr. A Thomas Hopkins (Acting) | October 1, 2014 – November 29, 2017 | Ash Carter | Barack Obama |
| Guy B. Roberts | November 30, 2017 – April 2, 2019 | Jim Mattis | Donald Trump |
| Alan Shaffer (PTDO) | April 2, 2019 – January 20, 2021 | Mark Esper | Donald Trump |
| Dr. Brandi Vann (Acting) | January 20, 2021 – August 4, 2021 | Lloyd Austin | Joe Biden |
| Deborah G. Rosenblum | August 4, 2021 – April 8, 2024 | Lloyd Austin | Joe Biden |
| Dr. Brandi Vann (Acting) | April 8, 2024 – Present | Lloyd Austin Pete Hegseth | Joe Biden Donald Trump |