The DNC debate took an unusual turn when the two remaining candidates, Bernie Sanders and Hillary Clinton, got into a row over Henry Kissinger. Sanders’ attack may have been a bit antiquated — Kissinger, 92, hasn’t officially held office for 40 years — but it serves as a starting point for something that the Vermont Senator lacks: a well-defined foreign policy platform.

PBS held the sixth Democratic debate in Milwaukee, Wisconsin, on Thursday night. One of Bernie Sanders’ more interesting moments came after he talked about Clinton’s praise 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. I am proud to say that Henry Kissinger is not my friend. I will not take advice from Henry Kissinger, and in fact, Kissinger’s actions in Cambodia when the United States bombed that country, and created the instability for the Khmer to come in, who butchered generations of people – one of the worst genocides in the world. So count me in as somebody who will not be listening to Henry Kissinger.”

According to Clinton’s book Hard Choices, during her tenure as Secretary of State, she regularly called on Kissinger’s advice when dealing with Chinese diplomats, particularly the Chinese state councilor, Dai Bingguo.

“Henry Kissinger had told me how highly he valued his relationship with Dai, whom he found to be one of the most fascinating and open-minded Chinese officials he had ever encountered.”

She also sought Kissinger’s help with eliciting an apology from Israel to Turkey in 2013 over the deaths of Turkish citizens on a Gaza flotilla, according to the New York Times.

Kissinger was a principle enemy of the American left for years. The assassination of Chilean leader Salvador Allende and the not-so-secret bombing of Cambodia and consequent genocide are among his critics’ accusations. Those are often weighed against Kissinger’s achievements, including normalizing diplomatic relations with China and secretly negotiating a peace treaty with Vietnam that lasted just long enough to withdraw American troops without incident (he won a Nobel Prize for his efforts there).

By calling out Hillary Clinton for her ties to Henry Kissinger, Sanders unveiled a critical difference between himself and Clinton, and the audience responded with cheers.

But Hillary had a comeback ready, correctly pointing out that “journalists have asked who you do listen to on foreign policy and we have yet to know who that is.”

Sanders snapped back, “well, it ain’t Henry Kissinger, that’s for sure.”

Sanders and Clinton in the middle of a heated exchange in Thursday nights debate. [Photo by Win McNamee/Getty Images]

Still, Clinton’s comeback hit on a weakness in Sanders’ platform: foreign policy. The Vermont senator cannot match Hillary’s experience — she served as Secretary of State from 2009 until 2013 — but he does have a voting record stretching back to 1991, when Sanders served in the House of Representatives, to give some hints about how he’d handle foreign relations.

He voted to use force to end the fighting in the Balkans and to destroy terrorist cells in Afghanistan in 2001 (although he regrets that President George W. Bush “abused” the authority). Bernie Sanders voted against the use of force for both the Gulf Wars (1991 and 2003) and has repeatedly said war should be the absolute last resort.

Sanders has also rallied against major free trade agreements, including the Trans-Pacific Partnership (TPP). Hillary Clinton also opposes the treaty, although she supported it when she was the secretary of state. Still, until now, Sanders has kept fairly quiet on the foreign policy front, and he has not named an adviser.

Is Bernie Sanders slam on Clinton’s ties with Henry Kissinger a sign that he’ll start getting serious about foreign policy or just a fun moment in the debate? He might not have Clinton’s experience, but he has the potential to become the anti-status quo candidate on foreign policy in addition to his anti-establishment domestic ideas.

[Photo by Brendan Smialowski/Getty Images]