When Cho Soon-ok was 17 in 1977, three men kidnapped and sold her to a pimp in Dongducheon, a town north of Seoul.

She was about to begin high school, but instead of pursuing her dream of becoming a ballerina, she was forced to spend the next five years under the constant watch of her pimp, going to a nearby club for sex work. Her customers: American soldiers.

The euphemism “comfort women” typically describes Korean and other Asian women forced into sexual slavery by the Japanese during World War II. But the sexual exploitation of another group of women continued in South Korea long after Japan’s colonial rule ended in 1945 — and it was facilitated by their own government.

There were “special comfort women units” for South Korean soldiers, and “comfort stations” for American-led U.N. troops during the Korean War. In the postwar years, many of these women worked in gijichon, or “camp towns,” built around American military bases.

Last September, 100 such women won a landmark victory when the South Korean Supreme Court ordered compensation for the sexual trauma they endured. It found the government guilty of “justifying and encouraging” prostitution in camp towns to help South Korea maintain its military alliance with the United States and earn American dollars.

It also blamed the government for the “systematic and violent” way it detained the women and forced them to receive treatment for sexually transmitted diseases.

In interviews with The New York Times, six former South Korean camp town women described how their government used them for political and economic gain before abandoning them. Encouraged by the court rulings — which relied on recently unsealed official documents — the victims now aim to take their case to the United States.

“The Americans need to know what some of their soldiers did to us,” said Park Geun-ae, who was sold to a pimp in 1975, when she was 16, and said she endured severe beatings and other abuse from G.I.s. “Our country held hands with the U.S. in an alliance and we knew that its soldiers were here to help us, but that didn’t mean that they could do whatever they wanted to us, did it?”

South Korea’s history of sexual exploitation is not always openly discussed. When a sociologist, Kim Gwi-ok, began reporting on wartime comfort women for the South Korean military in the early 2000s, citing documents from the South Korean Army, the government had the documents sealed.

“They feared that Japan’s right wing would use it to help whitewash its own comfort women history,” said Ms. Kim, referring to historical feuds between Seoul and Tokyo over sexual slavery.

In the aftermath of the Korean War, South Korea trailed the North in military and economic power. American troops stayed in the South under the U.N. flag to guard against the North, but South Korea struggled to keep U.S. boots on the ground.