Ash Carter, whose work bridging the worlds of technology and security helped to build a safer and more equitable world, has passed away. He was 68. His family announced he died after suffering a heart attack on Monday evening.

Carter was Belfer Professor of Science and Global Affairs and director of Belfer Center for Science and International Affairs. During a nearly four-decade-long career at HKS, he twice left to serve in government, eventually becoming U.S. secretary of defense from 2015 to 2017. 

“Ash Carter was a true patriot,” Harvard University President Larry Bacow said. “His counsel and service shaped America as we know it today—and made America better for all Americans. Losing him will have profound effects on Harvard Kennedy School and on the University, but it is our nation that has suffered the greater loss. We will do our best to honor Ash by remembering his commitment to democracy and by working together toward a more perfect union.” 

As secretary of defense, Carter helped lead the international coalition to destroy ISIS, designed and executed the strategic pivot to the Asia-Pacific region, and launched a defense cyber strategy. He opened all military positions to women, allowing them to serve in combat, and ended a ban on transgender troops serving in the military. 

In a previous stint in the Pentagon from 1993 to 1996 he was responsible for the Nunn-Lugar program that removed and eliminated nuclear weapons in former Soviet republics, including Russia, Ukraine, Kazakhstan, and Belarus. Carter and colleagues at the Belfer Center had helped to lay the groundwork for that denuclearization program, alerting the world to the dangers caused by the fall of the Soviet Union and arguing that fissile material from nuclear warheads could be turned into fuel for nuclear power plants. 

Ash Carter in Ukraine in 1995.
Ash Carter (center) looks on as U.S. Defense Secretary William Perry and Ukrainian Defense Minister Valeriy Shmarov shake hands after signing an agreement providing the Ukraine with assistance dismantling its nuclear weapons arsenal in 1995.

During a recent Forum event with Ukrainian President Volodymyr Zelenskyy, Carter remembered the poignant sight of former enemies who stared each other down across the Iron Curtain for decades, planting sunflowers together in a former Soviet missile field in Ukraine. 

“Ash was the best exemplar of what we aspire to for our faculty, fellows, and students,” said Graham Allison, Douglas Dillon Professor of Government and former dean of HKS and director of the Belfer Center. “He was an individual first and foremost committed to public service, to making a difference in making the world a safer place. He fulfilled that commitment by: advancing knowledge about the most important challenges—and what to do about them; serving in government when he had an opportunity; and preparing the next generation of students and fellows for leadership in government.”

He began his career in academia. After studying physics and medieval history at Yale University, he received his doctorate in theoretical physics from Oxford University, where he was a Rhodes Scholar. He served as a physics instructor at Oxford University, a postdoctoral fellow at Rockefeller University and MIT and an experimental research associate at Brookhaven and Fermilab National Laboratories before coming to HKS in 1984. He authored or coauthored 11 books and more than 100 articles on physics, technology, national security, and management.



During his time at the Pentagon, Carter was fond of saying how even when reaching the most remote military installation in places like Iraq or Afghanistan he would be greeted by a warm “Hello Professor Carter!” from former students turned soldiers. It was this long reach that convinced him to return to the Kennedy School after his years at the Pentagon, Kennedy School Dean Doug Elmendorf said in a statement.

“I want to offer my gratitude for his insight and wisdom, his unwavering commitment to trying to make the world better, his confidence that the Kennedy School can make an important difference in the world, his generous spirit toward his students and colleagues, and his warm and gracious friendship with me,” Elmendorf said. “I will miss him so much.”

Following the passing of Ash Carter (1954-2022), Belfer Professor of Technology and Global Affairs, director of the Belfer Center for Science and International Affairs, and former U.S. secretary of defense, hundreds of tributes came in from all over the world. Here are a few reflections from the Kennedy School community and beyond.

Others joined in remembering Carter on Tuesday, who is survived by his wife, Stephanie, and his children, Ava and Will.  

“He was a beloved husband, father, mentor, and friend. His sudden loss will be felt by all who knew him,” his family said in a statement. “He believed that his most profound legacy would be the thousands of students he taught with the hope that they would make the world a better and safer place.” 

“Today we mourn the passing of former Secretary of Defense Ash Carter and celebrate a leader who left America—and the world—safer through his lifetime of service,” former President Barack Obama, in whose administration Carter served, wrote on Twitter. “Michelle and I extend our heartfelt sympathies to Ash’s wife, children, and all those who loved him.” 


Samantha Power, a colleague both at Harvard Kennedy School and in government service, called it “an immeasurable loss.” “Devastated by the passing of my friend and close colleague,” Power, the administrator of the United States Agency for International Development, wrote on Twitter. "An epic public servant who dedicated his life to making our country safer, he also inspired the next generation ... to tackle the world’s hardest problems.” 

Those hard problems included making technological change positive for all. The Technology and Public Purpose project that Carter created following his return to the Kennedy School in 2017 attempted to address that challenge. “The arc of innovative progress has reached an inflection point,” the project’s mission statement reads. “It is our responsibility to ensure it bends towards public good.” 

“Rest in peace Ash Carter—colleague, friend, patriot, national leader,” Larry Summers, Charles W. Eliot University Professor, wrote on Twitter. “Along with the national security community, his Kennedy School and Belfer Center colleagues and students, I will miss Ash's wisdom, dedication and his leadership for our country. This is a very sad day.” 

“As his student at the Kennedy School, Ash Carter mentored me for a career in national security,” said Eric Rosenbach, co-director with Carter of the Belfer Center for Science and International Affairs. “A decade later in the Pentagon, as his chief of staff, Ash demonstrated to me why we need principled, indefatigable leaders who take on the toughest issues to keep America inclusive and strong. Back at the Kennedy School, he made me realize that people who both teach the next generation and lead the current one are truly unique. Ash was one of a kind, and I will miss him dearly.”

Ash Carter teaching in a classroom in 1985.
Ash Carter teaching at the Kennedy School in 1985.

This piece was also featured in the Winter 2023 Harvard Kennedy School Magazine.
Photos by Martha Stewart, Jessica Scranton, and R. D. Ward/Department of Defense

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