Hans Morgenthau
Hans Morgenthau was a German-born political scientist who founded modern American realism with his 1948 book Politics Among Nations.
Hans Morgenthau (1904–1980) was a German-Jewish political scientist who founded the school of thought known as classical realism in international relations. He fled Nazi Germany and reached the United States in 1937. In 1948 he published Politics Among Nations, the book that taught two generations of American diplomats and scholars how to think about power. Its central argument was that world politics is a permanent struggle for advantage, driven not by ideals but by human nature. People want to dominate, and the states they build inherit that drive. Morgenthau spent the rest of his career applying that idea, first as an adviser to the U.S. government and then as one of the most prominent critics of the Vietnam War.
How Morgenthau came to the United States
Morgenthau grew up in a Jewish family in the small German city of Coburg. He was an only child who later described himself as shy and lacking confidence. He studied law at the universities of Frankfurt, Berlin, and Munich, earned his doctorate in 1929, and worked as a lawyer and labor court judge in Frankfurt. When Hitler came to power in 1933, Morgenthau was teaching public law in Geneva. He stayed there until 1935, taught international law in Madrid for a year, and in 1937 emigrated to the United States without sponsors or connections.
He started at Brooklyn College, moved to the University of Kansas City, and in 1943 joined the University of Chicago, where he would teach for nearly thirty years. In 1946 he published Scientific Man versus Power Politics, which attacked the belief that reason and international law could restrain aggressive states. He treated his own experience under the Nazis as proof: appeals to law had not stopped Hitler. Two years later, Politics Among Nations turned that argument into a full theory of how states behave, and it became the standard textbook in international relations courses across the country.
What are Morgenthau's six principles of political realism?
The second edition of Politics Among Nations, published in 1954, opened with what became the book's most famous passage: six principles of political realism. The most important of them defines the core idea as "interest defined in terms of power." Under this framework, the purpose of foreign policy is to protect what a country actually needs, not to impose its values on other nations.
Morgenthau drew on a line of thinkers stretching back to Thucydides, through Machiavelli and Hobbes. All of them saw the desire for power as built into human beings, not as a flaw that better institutions could fix. Morgenthau's reasoning followed from that: since individuals compete for dominance, and individuals run governments, governments will compete for dominance too. No treaty or international body changes this.
The six principles also warn against confusing a country's own morality with universal moral law. Morgenthau believed that a state convinced of its own righteousness tends to overreach. Prudence, not righteousness, was the supreme political value in his system.
Why Morgenthau opposed the Vietnam War
Morgenthau served as a consultant to the State Department under Presidents Kennedy and Johnson. In 1965, as the Johnson administration escalated the war in Vietnam, Morgenthau broke with the government in public.
At a national teach-in in Washington, D.C. on May 15, 1965, he argued that the United States had no vital interest in Southeast Asia and that the war contradicted the realist principles he had spent his career defending. A month later, on June 21, he debated McGeorge Bundy, Johnson's national security adviser, on national television. Morgenthau made the case that matching commitments to real interests could mean refusing a war as easily as fighting one. The Johnson administration responded by ending his advisory role.
The episode showed that realism is not simply a philosophy of warmongering. Morgenthau used the same logic that justified defending vital interests to argue that the United States should not fight in Vietnam. His peers later ranked him as one of the most influential intellectual voices against the war.
How Morgenthau's realism differs from Kenneth Waltz's
A generation after Politics Among Nations, Kenneth Waltz kept realism's conclusion but changed its foundation. Morgenthau located the drive for power in human nature: people are flawed, and states reflect those flaws. Waltz argued that the cause is structural. Because no world government exists above states, they must compete for security regardless of what their leaders are like. Waltz called this structural realism, or neorealism, and it moved the argument from psychology to the design of the international system itself.
The debate between human nature and system structure still organizes the field of international relations. Morgenthau died in New York on July 19, 1980. His core ideas, that states pursue power and that prudence matters more than ideology in foreign policy, remain the foundation of the realist tradition he built.