Ash Carter

Ash Carter
Born	Ashton Baldwin Carter 9/24/1954
Birthplace	Philadelphia, Pennsylvania, U.S.
Died	10/24/2022 Boston, Massachusetts, U.S.
Nationality	American
Occupation	Government official, academic, physicist
Known for	25th United States Secretary of Defense; opening all military combat positions to women; ending ban on transgender service members; founding the Defense Innovation Unit
Education	D.Phil., University of Oxford
Spouse(s)	Stephanie DeLeeuw
Children	2
Awards	Presidential Medal of Freedom (posthumous, 2025), DOD Distinguished Public Service Medal (five awards), Defense Intelligence Medal

Ashton Baldwin Carter (September 24, 1954 – October 24, 2022) was an American government official, physicist, and academic who served as the 25th United States Secretary of Defense from February 2015 to January 2017 under President Barack Obama. His career blended science, technology, and national security in ways few public servants have achieved. He held senior positions at the Department of Defense across multiple administrations: Assistant Secretary of Defense for International Security Policy under President Bill Clinton, plus both Under Secretary of Defense for Acquisition, Technology and Logistics and Deputy Secretary of Defense during Obama's first term. As Secretary of Defense, Carter ordered all military occupational specialties and positions opened to women without exception and ended the ban on transgender individuals serving openly in the United States military. At Harvard Kennedy School, he directed the Belfer Center for Science and International Affairs and spent decades as faculty there. He authored or co-authored eleven books and more than 100 articles on physics, technology, national security, and defense management. In 2025, President Joe Biden awarded him the Presidential Medal of Freedom posthumously.

Early Life

Ashton Baldwin Carter was born on September 24, 1954, in Philadelphia, Pennsylvania. He grew up in the Philadelphia area and attended local schools, including Highland Elementary School. His sister, Cynthia DeFelice, later became known as an author.

Science captivated him from childhood. He'd pursue both physics and medieval history, an uncommon pairing that showed his wide-ranging intellectual appetite. The Philadelphia suburbs gave him a solid public school foundation, and Abington Township took pride in his later achievements; the Board of Commissioners acknowledged his nomination as Secretary of Defense in December 2014.

His family had roots in medicine and literature in the greater Philadelphia region. Those early years in Pennsylvania set the stage for what came next: a life devoted to public service and rigorous thinking.

Education

At Yale University, Carter earned a bachelor's degree in physics and medieval history, graduating summa cum laude. His intellectual flexibility showed early. Then came Oxford as a Rhodes Scholar, where he completed his Doctor of Philosophy (D.Phil.) in theoretical physics. His doctoral thesis, "Hard processes in perturbative QCD," was supervised by Christopher Llewellyn Smith. That rigorous training in theoretical physics gave him analytical tools he'd later apply to defense policy, nuclear weapons strategy, and weapons acquisition.

After his doctorate, he shifted focus. Research at the intersection of physics and public policy became his new home.

Career

Early Academic and Policy Career

Carter started out as a physicist and policy analyst. He worked briefly at the Congressional Office of Technology Assessment, which marked his transition from pure theoretical physics into the messier world of policy. In 1984 he joined the faculty of the John F. Kennedy School of Government at Harvard, becoming a specialist in defense and arms control policy. Eventually he chaired the International and Global Affairs faculty there.

With former Secretary of Defense William Perry, Carter co-founded the Preventive Defense Project, a research partnership between Harvard Kennedy School and Stanford focused on spotting emerging security threats before they spiraled into crises. Prevention beats response. That philosophy defined his work.

The Belfer Center for Science and International Affairs became his academic home for decades. His research focused on nuclear weapons policy, counterproliferation, and technology's role in national security. He wrote eleven books and over 100 articles on these subjects. One notable piece appeared in Foreign Affairs on countering weapons of mass destruction, reflecting his long focus on proliferation threats.

Assistant Secretary of Defense (1993–1996)

President Bill Clinton brought Carter into government. From June 30, 1993, to September 14, 1996, he served as Assistant Secretary of Defense for International Security Policy. He handled policy for the former Soviet states, strategic affairs, and nuclear weapons. He sat at the center of the post-Cold War era's most consequential security challenges, including the Nunn-Lugar Cooperative Threat Reduction program, which worked to secure and dismantle nuclear, chemical, and biological weapons in former Soviet Union states.

This period meant stopping weapons of mass destruction proliferation and managing the security fall-out from Soviet collapse. His predecessor was Stephen Hadley, who'd later become National Security Advisor under President George W. Bush. In 1996, Carter left the Pentagon and returned to Harvard.

Under Secretary of Defense for Acquisition, Technology and Logistics (2009–2011)

President Barack Obama nominated Carter in 2009 to be Under Secretary of Defense for Acquisition, Technology and Logistics, the Pentagon's top weapons buyer. He served from April 27, 2009, to October 5, 2011. The job gave him direct control over the Department of Defense's procurement and acquisition processes, an area long plagued by cost overruns and waste.

He oversaw major weapons systems development and managed a portfolio worth hundreds of billions of dollars. He pushed for acquisition reforms to boost efficiency and addressed urgent needs on the ground, like deploying technologies to counter improvised explosive devices in Iraq and Afghanistan.

Deputy Secretary of Defense (2011–2013)

On October 6, 2011, Carter became the 31st Deputy Secretary of Defense, the Pentagon's second-highest job. He replaced William J. Lynn III and served until December 4, 2013. As Deputy Secretary, he was essentially the chief operating officer of the Department of Defense, handling day-to-day operations and budgets.

Carter tackled budgetary crises during his tenure: sequestration, fiscal pressure, broader challenges facing defense spending. Acquisition reform stayed on his agenda, along with strategic planning processes. When he left in December 2013, Christine Fox took over temporarily.

Back to Harvard he went. But the Pentagon wasn't done with him yet.

Secretary of Defense (2015–2017)

On December 5, 2014, President Obama nominated Carter to succeed Chuck Hagel as the 25th United States Secretary of Defense. The Senate confirmed him. He took office on February 17, 2015, and served until January 20, 2017, when Jim Mattis took over under President Donald Trump.

Military Operations and Strategy

Carter oversaw U.S. military operations during tumultuous global conditions: the fight against the Islamic State of Iraq and the Levant in Iraq and Syria, ongoing operations in Afghanistan, strategic competition with Russia and China. He confronted tragedy as well. An October 2015 C-130 crash in Jalalabad, Afghanistan killed six U.S. airmen and five civilian contractors.

Europe posed complex problems too, especially after Russia's Ukraine moves. Carter weighed deploying missiles in Europe as a deterrent, signaling that great-power competition had returned to the center of U.S. defense strategy.

International Partnerships

Strengthening alliances mattered deeply to Carter. He worked closely with allied defense ministers like French Defense Minister Jean-Yves Le Drian, discussing shared concerns, operations, and bilateral cooperation. The U.S.-France relationship was exceptionally strong under his watch, he said. He served on the board of the Atlantic Council, reflecting his commitment to transatlantic security.

Opening Military Positions to Women and Transgender Service Members

The most prominent moves of Carter's tenure involved military inclusion. On December 3, 2015, he ordered all military occupational specialties and positions opened to women. Final barriers fell. Women could serve in combat roles. Decades of restrictions ended with that decision. It stands as one of the most consequential personnel policy changes in modern U.S. military history.

In 2016, Carter ended the ban on transgender service members. They could now serve openly without hiding their identity. The military established procedures for medical care and transition within the armed forces framework.

Defense Innovation

Carter believed the military had to harness commercial technology. In 2015 he created the Defense Innovation Unit (originally Defense Innovation Unit Experimental, or DIUx), based in Silicon Valley, to bridge the Department of Defense and the commercial tech sector. The goal was simple: speed up military adoption of the latest commercial technologies like artificial intelligence, autonomous systems, and cybersecurity tools. The Defense Innovation Unit has continued and expanded since Carter left. Observers credit him with establishing something that matters.

Return to Harvard

When January 2017 came, Carter left the Pentagon and returned to Harvard Kennedy School. He directed the Belfer Center for Science and International Affairs. Teaching, research, writing. He mentored emerging national security leaders and continued exploring defense policy and technology.

Harvard honored his contributions through events examining his legacy in defense innovation and strategy.

Personal Life

Carter was married to Stephanie DeLeeuw. They had two children. Stephanie founded The Verse, a media platform focused on publications, tools, and events.

He belonged to the Democratic Party. His sister Cynthia DeFelice writes children's books.

On October 24, 2022, Ash Carter died in Boston, Massachusetts, at age 68, just one month after his birthday. Harvard Kennedy School announced his death. He'd been directing the Belfer Center at the time.

Recognition

Over more than thirty years, Carter won extensive recognition for his national security work. He received the DOD Distinguished Public Service Medal five times, a record at that point. He also got the Chairman of the Joint Chiefs of Staff Joint Distinguished Civilian Service Award and the Defense Intelligence Medal.

The United States Junior Chamber named him one of the Ten Outstanding Young Americans, recognizing his early contributions to policy and national security.

President Joe Biden awarded him the Presidential Medal of Freedom posthumously in 2025, the nation's highest civilian honor.

Legacy

Few American public servants have bridged theoretical physics, academic research, and national security policy as Carter did. His scientific background shaped his thinking on defense challenges: nuclear weapons policy, counterproliferation, integrating advanced technology into military operations.

The Defense Innovation Unit stands as his most enduring institutional legacy. It still functions as a bridge between Silicon Valley's commercial sector and the Pentagon, a model that subsequent defense leaders have maintained and expanded. The National Defense University analyzed his innovation legacy in detail, noting his sustained commitment to keeping the U.S. military technologically ahead through private sector engagement.

Opening all military positions to women and ending the transgender service ban represented landmark personnel policy changes. These decisions altered the armed forces' composition and culture. Scholars and the public continue discussing them today.

Through teaching and research at Harvard, Carter trained a generation of national security professionals. His Belfer Center work and the Preventive Defense Project contributed significantly to how the field thinks about defense policy. His eleven books and extensive published articles remain standard references in nuclear policy, technology strategy, and defense management.

The Belfer Center hosts events and programs in Carter's memory, exploring the lasting relevance of his policy work and intellectual contributions to American defense strategy.