The Under Secretary of Defense for Policy in the U.S. Department of Defense is one of the biggest – and hardest – jobs in Washington. Colin Kahl served in that role for more than two years. From April 2021 to July 2023, he was the principal adviser to Secretary of Defense Lloyd Austin for all matters related to national security and defense policy, oversaw the writing of the 2022 National Defense Strategy, which focused on the “pacing challenge” posed by China, and he led the Department’s response to Russia’s full-scale invasion of Ukraine, among other international crises. He also led other major defense diplomacy initiatives, like U.S. efforts to revitalize the NATO alliance. Kahl has had a long career in government and public service. During the Obama administration, he served as Deputy Assistant to the President and National Security Advisor to then-Vice President Biden. Before that, he served in the Pentagon as Deputy Assistant Secretary of Defense for the Middle East for nearly three years.Just Security’s Co-Editor-in-Chief Tess Bridgeman recently sat down with Kahl, who is now a Senior Fellow at Stanford University’s Center for International Security and Cooperation, for an exit interview.Show Notes: Colin Kahl (@ColinKahl)Paras Shah (@pshah518) Tess Bridgeman (@bridgewriter) Just Security’s China coverage  Just Security’s Russia-Ukraine war coverageJust Security’s artificial intelligence coverageMusic: “The Parade” by “Hey Pluto!” from Uppbeat: https://uppbeat.io/t/hey-pluto/the-parade (License code: 36B6ODD7Y6ODZ3BX)Music: “Lilac” by “Night Drift” from Uppbeat: https://uppbeat.io/t/night-drift/lilac (License code: CFXEBHMVBA8FXVNC)