PARIS — William Pfaff, an international affairs columnist and author who was a prominent critic of American foreign policy, finding Washington’s intervention in world affairs often misguided, died on Thursday in a hospital here. He was 86.

His wife, Carolyn Pfaff, said the cause was a heart attack after a fall.

Mr. Pfaff, who moved to Paris in 1971, wrote a syndicated column that appeared for more than 25 years in The International Herald Tribune, now The International New York Times. He was a longtime contributor to The New Yorker, The New York Review of Books and other publications, the articles informed by his deep knowledge of history and philosophy.

Mr. Pfaff (pronounced FAFF) also wrote eight books, which further examined American statecraft as well as 20th-century Europe’s penchant for authoritarian utopianism. In “The Bullet’s Song: Romantic Violence and Utopia,” published in 2004, he examined what drove European intellectuals to embrace communism, fascism and Nazism.

In “Barbarian Sentiments: America in the New Century” (1989), he argued that the United States had historically harbored unrealistic assumptions about its benevolence in its foreign policy, often with disastrous results. The book was a finalist for the National Book Award. “In fresh, lucid and arresting prose,” the citation said, Mr. Pfaff “articulates America’s geopolitical illusions.”