We study how two significant conflicts between China and the U.S.—the Korean War and the current trade war—affect global supply chains. Using hand-collected data, we find that the death toll from the Korean War in a chairperson's city of origin strongly influences Chinese firms' selection of U.S. suppliers today. Moreover, the current trade tensions reactivate memories of wartime trauma, significantly amplifying their negative effects. We identify two key mechanisms driving this change: Chinese retaliatory tariffs and increased media coverage of the Korean War within China. A variety of empirical tests suggest that our findings are causal and are not a result of U.S. suppliers' choice.