Mark Milley is a U.S. Army general who serves as the 20th Chairman of the Joint Chiefs of Staff, the nation’s highest-ranking military officer, and the principal military advisor to the President, Secretary of Defense, and National Security Council. The general earned his "tabs" as an Army Ranger and a Green Beret, and he has extensive combat experience, taking part in operations in Panama, the Balkans, Iraq, and Afghanistan. Before his current position, Milley served as the 39th Chief of Staff of the Army, the service's top officer. During this 2015-2019 tenure, Milley focused heavily on modernization efforts for the Army, which included a new command designed to consolidate the methods that deliver Army capabilities. Before that, he'd been in the military for 35 years, holding multiple command and staff positions in eight divisions and Special Forces. In addition to his undergraduate degree, Milley has a master’s degree from Columbia University and a master's degree from the U.S. Naval War College. He is also a graduate of the MIT Seminar XXI National Security Studies Program. Among his numerous honors and recognitions, the four-star general has been awarded the Defense Distinguished Service Medal, the Army Distinguished Service Medal, and the Bronze Star Medal.

A rarity among senior military officers, Milley did not attend one of the service academies, but rather is an Ivy League graduate who enrolled in Princeton University in 1976. While he grew up in a working-class neighborhood in Boston, good grades and a talent for playing hockey led to him being recruited by the Tigers, who offered him a scholarship as a hockey player. On top of sports, Milley also got his first taste of military service in school. At Princeton, he joined the Reserve Officers' Training Corps (ROTC) program. In 1980, after completing a 185-page senior thesis titled, "A Critical Analysis of Revolutionary Guerrilla Organization in Theory and Practice," he graduated with a Bachelor of Arts in politics from Princeton University. Upon graduation, he was commissioned as an officer in the U.S. Army.

By all accounts, Milley enjoys visiting campus when possible. During the past few years, he's often returned to deliver the address at the university’s Joint ROTC Officer Commissioning Ceremony, which—considering his status as the highest-ranking military officer—is a tremendous honor for the Princeton community. In his May 2022 address to the soon-to-be officers, he reminded them of their duty to serve others and of their allegiance to the U.S. Constitution: “You are entering not a job, you’re entering a calling,” he said. He also laid out the landscape of military threats which the Princeton graduates were entering, calling out Russia’s invasion of Ukraine as “a gross violation” of the principles of international relations put into place after World War II that could lead to further conflict if allowed to stand. “It’s incumbent upon you and I, those of us in uniform, to protect this group out here,” he said, referring to the guests in attendance. “And we will do that no matter what the cost to ourselves. You are entering not a job; you’re entering a calling.”