The United States’ role in Cambodia’s troubled past briefly took centre stage at the latest Democratic debate on Thursday night when presidential hopeful Bernie Sanders attacked his rival Hillary Clinton’s links to former US Secretary of State Henry Kissinger, who oversaw the carpet bombing of the Kingdom in the 1970s.

Sanders, a senator from Vermont who has been seen as relatively weak on foreign policy compared to Clinton, a former secretary of state, sought to tarnish his opponent with the former top diplomat’s unpopular legacy by citing her admission that Kissinger was “a friend” whose counsel she “relied on” as secretary of state, which she wrote in a review of Kissinger’s book World Order in 2014.

Declaring he was “proud” not to be Kissinger’s friend, Sanders recalled Cambodia’s descent into war. “I will not take advice from Henry Kissinger and, in fact, in Kissinger’s actions in Cambodia, when the United States bombed that country, overthrew Prince Sihanouk and 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, immediately took aim at Sander’s foreign policy credentials. “Well, I know journalists have asked who you do listen to on foreign policy and we have yet to know who that is,” she retorted.