On May 7, 1984, seven chemical companies, including Dow and Monsanto, agree to pay $180 million to thousands of Vietnam veterans exposed to the chemical herbicide Agent Orange during the war. Lawyers for the two sides announced the surprise out-of-court settlement on the day jury selection was to begin in the case.

U.S. military forces sprayed nearly 20 million gallons of herbicides over Vietnam, Cambodia and Laos from 1961 to 1971 during Operation Ranch Hand, with the aim of destroying forest cover and crops being used by North Vietnamese and Viet Cong troops. The chemical Agent Orange made up nearly two-thirds of the herbicides used.

Although its active ingredients caused plants to lose their foliage, Agent Orange also included significant amounts of dioxin, a “persistent organic pollutant” which could persist for years in the environment through soil, lake and river sediments, and in the food chain. Dioxin contaminants are linked to long-term health issues including type 2 diabetes, immune system dysfunction, nerve disorders, muscular dysfunction, hormone disruption and heart disease—with even more dire effects for developing fetuses. After the war, returning Vietnam veterans and their families began reporting these issues.

A class-action lawsuit was filed in 1979 on behalf of 2.4 million veterans exposed to Agent Orange, culminating in a surprise settlement five years later, with the seven large chemical companies that manufactured the herbicide agreeing to pay $180 million in compensation to the veterans or their children. Lawyers representing the veterans, in turn, dropped damage claims against these defendant companies.

The manufacturers had maintained the “government contractor” defense—that because they had been following government orders to produce Agent Orange, the government should be held liable. A few months after the settlement, the Justice Department refuted that claim, pinning the blame on the manufacturers’ “profit, not compulsion or patriotism.” In 1991, President George H.W. Bush signed into law the Agent Orange Act of 1991, mandating that diseases associated with Agent Orange and other herbicides be treated as the result of wartime service, acknowledging responsibility on the part of the Department of Veterans’ Affairs.

However, none of the above bills or settlements sought to protect or compensate the Vietnamese victims of Operation Ranch Hand. According to the Vietnamese government, as many as 400,000 Vietnamese people suffered death or permanent injury, while another 2 million may have suffered from illnesses brought on by Agent Orange. A class-action lawsuit brought by Vietnamese citizens in 2004 against more than 30 chemical companies claimed that the use of Agent Orange constituted a violation of international law, but that suit was rejected on final appeal in 2008 by the same U.S. District Judge who presided over the U.S. veterans’ lawsuit.