Bangchen Ruan is a Ph.D. candidate in the Department of Political Science at the University of Chicago, specializing in international relations and security studies. His research examines the strategic logic of territorial behavior among great and major powers, with a particular focus on the geospatial foundations of state survival. His work argues that states value territory hierarchically under existential threat, prioritizing the protection of territorially concentrated core areas that sustain sovereign autonomy and organized resistance. His dissertation develops a theory of strategic depth to explain why some states pursue core relocation as a strategy for preserving strategic depth, while others defend their core areas in place through frontline defense, expansion, or alliances. More broadly, his research contributes to debates on territorial value, the survival assumption in international relations theory, and military strategy across conventional and nuclear eras. His broader interests include international security, coercion, political geography, and grand strategy. Ruan received an M.A. from the Committee on International Relations at the University of Chicago in 2020 and a B.A. in Politics from Centre College in 2019.