In Korea, Vietnam, and the Persian Gulf War, 80% or more of all fatalities were white. Why is that?

http://fas.org/sgp/crs/natsec/RL32492.pdf

Page 10.

It's a fact more whites died than members of any other ethnic group. I can think of a number of possible explanations, the foremost being that perhaps 80% of the armed forces in those eras were white. That's not how I remember it though. I remember being a part of a multicultural group of people, all eager to serve our country. I did not once feel like I was in a majority by being white of skin. (*Although I consider myself of American Indian heritage, the majority of my ancestors were white so I check that box on such questions.)