The enduring connection between Harvard and the U.S. military owes not just to the service of thousands of students and graduates through the decades but also to shared values, President Alan Garber said on Tuesday.

Garber, together with leaders at the Kennedy School and the Belfer Center, spoke at a reception at Loeb House for this year’s National Security Fellows, a dozen active-duty officers holding the ranks of lieutenant colonel, commander, and colonel. The fellows spent the academic year taking classes, leading seminars, and participating in working groups on topics ranging from the future of diplomacy to atomic power and weapons.

“We are very, very deeply connected with the military,” Garber said. “Harvard students and alumni have served going back to King Philip’s War, in 1675, before there was a United States. It’s not only a reflection of the age of Harvard — it’s a reflection of common values. There’s so much we stand for in common, and a lot of it has to do with service and service to the country, which can take many different forms.”

Garber, an M.D. who practiced 25 years in a VA hospital, said that his clinical work exposed him not only to his patients’ experiences, but also to their character.

“It was one of the most meaningful experiences in my life,” he said. “I treated veterans who served during wartime from World War II right up until I left in 2011, and their stories were remarkable. Stories of courage, stories of learning how to work together and what it meant to be part of a team.”

The National Security Fellowships were founded 42 years ago by Graham Allison, Douglas Dillon Professor of Government and former Kennedy School dean, and the late Ernest May. The program is among the School’s earliest executive education initiatives.

“This program is a crown jewel in so many ways, bringing people of accomplishment and experience into our environment, where we hope you learn from us and we certainly learn from you,” Garber said, adding: “I want to thank you for spending your time with us.”

Harvard’s president was joined by Allison and Meghan O’Sullivan, director of the Belfer Center for Science and International Affairs, which hosts the program, in thanking the fellows for their service to the country and for their contributions to the University community since they arrived in the fall. Fellows bring a unique perspective to Harvard, O’Sullivan said.

“We are a place where we value the bridge between practice and ideas and scholarship, and you personify that,” said O’Sullivan, who served as deputy national security adviser during the George W. Bush administration. “We talk a lot about national security, strategy, and grand strategy, and you’ve actually lived it. You’ve made decisions under pressure. When you step into our classrooms or our common rooms, you are bringing a commodity that is highly prized.”

O’Sullivan, the Kirkpatrick Professor of the Practice of International Affairs, said that she routinely asks graduates about the most powerful moments in their time at the Kennedy School, and that the answers regularly point to interactions with service members.

“More than half of our students are from other countries and they never imagined they would meet somebody in the U.S. military, they never imagined they would become friends with someone in the U.S. military,” she said. “Suddenly, they’re in a position where, when they hear about the U.S. military, they’re going to think of your faces, personifying one of our greatest institutions in a way that is absolutely priceless — for them and for our country.”

Allison noted that Harvard has 18 Medal of Honor recipients, more than any other educational institution outside of the service academies. The names of hundreds of the University’s war dead adorn the walls of Memorial Hall, which records Union soldiers who fell in the Civil War, and Memorial Church, which was built to honor the dead of World War I and now also includes service members who died in World War II, the Korean War, and Vietnam.

Several speakers described the moment as bittersweet, including Eric Rosenbach, director of the fellowship and a senior lecturer of public policy at the Kennedy School. The reception marked the approaching end of the program for current fellows as well as an upcoming pause in bringing new National Security Fellows to campus. The government announced in February that it would end professional military education, fellowship, and certificate programs with Harvard and other Ivy League schools.

Speakers described the change as a hiatus, however, rather than the program’s termination. They also encouraged current fellows to stay in touch, both with one another and with faculty associated with the program. This year’s cohort will join a network of more than 800 National Security Fellows who have come through the program since its start in 1984.

“You are part of our fabric,” O’Sullivan said. “You will be part of our fabric when you leave these doors.”