He was the only ethnic Hmong to attain the rank of General officer in the Royal Lao Army, and he was loyal to the King of Laos while remaining a champion of the Hmong people. During the 1960s/70s, he commanded the Secret Army, also known as the Hmong Army, a highly-effective Central Intelligence Agency-trained and supported force that fought against the Pathet Lao and People's Army of Vietnam. Vang's ethnic Hmong and Laotian veterans and their refugee families who served in the U.S. "Secret Army" were eventually granted the status of political refugees by the United Nations because of alleged persecution by the Lao Marxist government and communist Vietnam who took control in 1975. The Lao and Hmong refugees were allowed to resettle in the United States, France, Australia, New Zealand and elsewhere. Many of Vang's former veterans formed the Lao Veterans of America, Inc. and the Lao Veterans of America Institute, with offices in Fresno, California, Washington, D.C. and other locales.