The Sydney Morning Herald reported that the U.S. is seeking $500 million in repayment from Cambodia for a Vietnam War-era loan, primarily in the form of excess maize. According to the SMH:
The debt started out as a US$274 million loan mostly for food supplies to the then US-backed Lon Nol government but has almost doubled over the years as Cambodia refused to enter into a re-payment program.
As the article also pointed out, many people across the political spectrum are outraged by the request, given the role the U.S. played in bombing Cambodia. According to Yale historian Ben Kiernan, from 1965-73 U.S. planes dropped nearly 2.8 million tons of bombs over the eastern part of the country. This was part of a larger war meant to deny communist troops and supplies from North Vietnam from reaching the South via Laos and Cambodia.
Although casualty estimates from war are notoriously difficult, U.S. bombing was estimated to have killed 50,000 to perhaps hundreds of thousands of Cambodians, many of them civilians. Furthermore, historians such as Kiernan have argued that without the bombing, the Khmer Rouge might not have grown as much as it did, with people radicalized against U.S. brutality and into the arms of the K.R. Their rise to power, of course, led to more atrocities and genocide only a few years later.
Given all of that, it seems preposterous, or at least tone-deaf, for the U.S. to request repayment. And it’s not just Cambodians who think so. Also noted in the SMH article was a quote from James Pringle, a former Reuters bureau chief in Ho Chi Minh City, who was near Cambodia during the war:
“Cambodia does not owe a brass farthing to the US for help in destroying its people, its wild animals, its rice fields and forest cover.”

U.S. bombing of Cambodia from 1965-1973 (by Taylor Owen and Ben Kiernan). Source.