A Canadian political scientist specializing in International security, Foreign policy analysis, Political psychology, and International relations theory, Welch is author of two award-winning books—"Justice and the Genesis of War" (Cambridge University Press, 1993) and "Painful Choices: A Theory of Foreign Policy Change" (Princeton University Press, 2005), and coauthor with Joseph Nye of the widely used International Relations Textbook, "Understanding Global Cooperation and Conflict" (Pearson Longman, 2016), now in its tenth edition.