The passing of the monumental international-relations theorist Kenneth Waltz last week has already attracted two commemorations in these spaces. His sober yet unconventional realist thought appeared in The National Interest on several occasions. The most recent, in August 2010, was a debate with Stanford University scholar Scott D. Sagan on the merits of working toward a world without nuclear weapons.

Sagan suggested such a world would be safer. Waltz disagreed, arguing that while shrinking nuclear arsenals was prudent, “abolishing the weapons that have caused sixty-five years of peace would . . . among other things, make the world safe for the fighting of World War III.” Moreover, he said, no amount of American nuclear disarmament would make America’s enemies follow suit, as they fear America’s conventional might far more than its nuclear arsenal, and “nuclear weapons are the only weapons capable of dissuading the United States from working its will on other nations.”

Waltz applied this logic consistently: his last major article was a 2012 essay for Foreign Affairs that argued the Middle East might be a bit safer if the mullahs of Iran got their own bomb. The idea inspired so much controversy that Israeli prime minister Benjamin Netanyahu would even denounce it on the floor of the United Nations. Yet Waltz stuck to his guns.

Sagan and Waltz’s brisk exchange continues to be relevant as the United States weighs further reductions in its nuclear arsenal—and warns Iran that it will take no options off the table in preventing their acquisition of the bomb. Click here to go to the article.

Robert W. Merry is editor of The National Interest.

Image: theory-talks.org/Peer Schouten.