The late Christopher Hitchens penned an exceptionally important book in 2001 titled The Trial of Henry Kissinger.

In it, Hitchens argued that the former national security adviser and secretary of state for Presidents Richard Nixon and Gerald Ford should be prosecuted “for war crimes, for crimes against humanity, and for offenses against common or customary or international law, including conspiracy to commit murder, kidnap, and torture.”

Hitchens was a brilliant polemicist who loved to stir controversy (and who fell out with The Nation during post-9/11 debates about George W. Bush’s “war on terror” and defending civil liberties). But The Trials of Henry Kissinger was more than an argument; it was a detailed indictment (“using only what would hold up in international courts of law”) of an official who Hitchens accused of authorizing atrocities against Bangladesh, Chile, Cyprus, East Timor, Indochina, and the Kurds of Iraq. It was well reviewed, with the San Francisco Chronicle hailing Hitchens for presenting “damning documentary evidence against Kissinger in case after case,” and London’s Sunday Times describing the book as “a disturbing glimpse into the dark side of American power, whose consequences in remote corners of the globe are all too often ignored. Its countless victims have found an impassioned and skillful advocate in Christopher Hitchens.”

Despite the attention it received, the book did not lead to the prosecution of Kissinger. Nor did it spark all of the formal and official debates that Hitchens invited.

On Thursday night, however, Democratic presidential candidates Hillary Clinton and Bernie Sanders did debate Kissinger’s legacy in one of the most remarkable exchanges of modern presidential politics.

It was an exchange Hitchens would have relished.

In the foreign-policy section of the debate, after the candidates had clashed over a number of issues, Sanders asked if he might add a brief final word of to explain “where the secretary and I have a very profound difference.”

“[In] the last debate and I believe in her book—very good book, by the way…she talked about getting the approval or the support or the mentoring of Henry Kissinger. Now, I find it rather amazing, because I happen to believe that Henry Kissinger was one of the most destructive secretaries of state in the modern history of this country,” said the senator, to loud applause.

“I am proud to say that Henry Kissinger is not my friend,” continued Sanders. “I will not take advice from Henry Kissinger. And in fact, Kissinger’s actions in Cambodia, when the United States bombed that country, overthrew Prince Sihanouk, created the instability for Pol Pot and the Khmer Rouge to come in, who then butchered some 3 million innocent people, one of the worst genocides in the history of the world. So count me in as somebody who will not be listening to Henry Kissinger.”

Clinton countered with a dig at Sanders. “Well,” she said, “I know journalists have asked who you do listen to on foreign policy, and we have yet to know who that is.”

“Well, it ain’t Henry Kissinger. That’s for sure,” replied Sanders.

“That’s fine. That’s fine,” said Clinton. “You know, I listen to a wide variety of voices that have expertise in various areas. I think it is fair to say, whatever the complaints that you want to make about him are, that with respect to China, one of the most challenging relationships we have, his opening up China and his ongoing relationships with the leaders of China is an incredibly useful relationship for the United States of America. So if we want to pick and choose—and I certainly do—people I listen to, people I don’t listen to, people I listen to for certain areas, then I think we have to be fair and look at the entire world, because it’s a big, complicated world out there.”

“It is,” injected Sanders.

Clinton was now scrambling to put Kissinger in perspective. “And, yes,” she said, “people we may disagree with on a number of things may have some insight, may have some relationships that are important for the president to understand in order to best protect the United States.”

Sanders was having none of that explanation, suggesting that his historical perspective was “very different.”

“Kissinger was one of those people during the Vietnam era who talked about the domino theory. Not everybody remembers that. You do. I do. The domino theory, you know, if Vietnam goes, China, da, da, da, da, da, da, da. That’s what he talked about, the great threat of China,” said Sanders. “And then, after the war, this is the guy who, in fact, yes, you’re right, he opened up relations with China, and now pushed various type of trade agreements, resulting in American workers losing their jobs as corporations moved to China. The terrible, authoritarian, Communist dictatorship he warned us about, now he’s urging companies to shut down and move to China. Not my kind of guy.”

And rightly so, for reasons that Christopher Hitchens well documented.