Why are there many Miao people in America?

Miao people in the United States, including overseas Miao people, supported more than 20 thousand Miao special forces in Laos against the pro-Vietnamese regime during the US-Vietnam War. Led by Miao and General Bao Wang. After the United States withdrew its troops from Vietnam, the current regimes in Vietnam and Laos launched large-scale liberation wars. Miao special forces were defeated and slaughtered and fled to Thailand. With the help of Thailand and the United Nations, they were arranged to be refugees in many western European countries, among which the United States received the most. These Miao people moved from Yunnan and Guizhou in China in the Ming and Qing Dynasties, and then moved to Laos. Just like the Miao people in China, if you don't know, you can find out why there are so many Miao people in many overseas countries by Baidu newspaper or national united front.