You might think a realist like me would nod in approval. Don’t realists think that power is all that matters and that norms, rules, and institutions have little impact on what states—and especially major powers—do? If that’s what you were taught in your introduction to international relations class, go back to your instructor and request a refund. Yes, realism does view power as the most important factor in world politics, and it maintains that powerful states have the greatest impact on the institutions that prevail at any given point in time. Realists also stress that because there is no central authority to enforce compliance, states can defy the rules if they wish. But sophisticated realists like Hans Morgenthau, Robert Gilpin , Henry Kissinger , Stephen Krasner , and even John Mearsheimer also emphasize that any system of interdependent states cannot function without a set of rules and that even powerful states will pay a price if they defy existing rules too often or too egregiously.

There are many things that U.S. President Donald Trump doesn’t understand about world politics—which is astonishing given that he’s in his second term at the White House—and one of them is the importance of international institutions. Institutions are rules, and Trump’s contempt for rules predates his entry into politics. He has long seen norms, laws, and rules as pesky constraints that sometimes prevent him from taking whatever he wants, and he’s brought that attitude to foreign policy. Whether he’s accepting lucrative emoluments from foreign governments, threatening to seize Greenland and annex Canada, or bullying foreign visitors in the Oval Office, Trump sees no norm as beyond challenge, no agreement as sacrosanct, and no global institution as worth investing in or defending.

There are many things that U.S. President Donald Trump doesn’t understand about world politics—which is astonishing given that he’s in his second term at the White House—and one of them is the importance of international institutions. Institutions are rules, and Trump’s contempt for rules predates his entry into politics.