Prof. Tsuruoka studied for his undergraduate degree at Keio University, where he gained his master’s degree. He also spent time at Georgetown University before completing a PhD in War Studies at King’s College, London. From 2009 to 2017, he was a researcher at the National Institute for Defense Studies, with a stint in Brussels as a specialist at the Japanese Embassy to Belgium, working alongside NATO. During this time, he served as Deputy Director of the International Policy Division in the Bureau of Defense Policy, Ministry of Defense, and as a visiting researcher at the Royal United Services Institute in the United Kingdom and the Australian National University.