New CFR Book by David Sacks Details the Life and Legacy of Hans Morgenthau

“Americans owe it to themselves to take heed of Morgenthau’s sober vision of international politics. There is no better teacher of realism than Hans Morgenthau, the man who literally wrote the book on great-­power competition,” writes David Sacks, senior fellow for Asia studies at the Council on Foreign Relations (CFR), in his new book, The Realist: Hans Morgenthau and the Purpose of American Power. “To understand Morgenthau, his ideas, and his life is to understand how we got here and where we are going.” 

In the first full-length biography of Hans Morgenthau, the founder of modern realism, Sacks follows him from Coburg, Germany, where the rise of Nazism shaped his worldview, to his exile in the United States, where he wrote Politics Among Nations in 1948—one of the most influential books on international politics. Sacks examines how Morgenthau applied his pioneering theory to contemporary Cold War debates, above all the Vietnam War, where he became one of the earliest and most prominent critics of U.S. intervention.  

Sacks asserts that Morgenthau’s thinking is as relevant as ever. With the Russian invasion of Ukraine and China seeking to displace U.S. influence in the world, “great-power competition has returned with a vengeance and America’s ability to successfully navigate it will determine the complexion of this century.” 

Realism is often derided as an amoral theory, but Sacks stresses Morgenthau’s deep ethical concerns, noting “he believed that norms and moral principles played a vital role in keeping the inevitable struggle for power within tolerable bounds by delineating practices that were off limits. At the same time, though, these rules and norms were only as strong as the power that underwrote them.” 

“David’s thorough profile of Hans Morgenthau is a timely and engrossing account of the founder of modern realism,” said CFR PresidentMichael Froman, “In the context of today’s changing world order, Morgenthau’s teachings and insights serve as a guide into what realism is and what it is not.” 

Sacks explains that for Morgenthau, the United States “stood alone—it was truly sui generis. Great nations were great not just because they had immense power but because they married that power to purpose.” Morgenthau argued that American power had to be put in service of preserving “democracy and liberty at home, so that the nation could stand as an example for the rest of the world.” 

“Through intensive research and interviews, David’s book provides a new look into the life of Hans Morgenthau, the man who revolutionized international relations,” said CFR Senior Vice President of Studies Shannon K. O’Neil. “This is required reading for all who seek to understand how the field has become what it is today.” 

“It is hard to appreciate just how much Morgenthau shaped the debate over U.S. foreign policy,” writes Sacks. “Now, however, nobody pretends power politics have been vanquished by law or by treaty, by science or technology, by moral evolution or social revolution. Morgenthau’s ideas have been fully absorbed into mainstream political discourse, the best evidence of his impact.”