When former secretary of state colin powell asked, "why did you serve a nation that did not serve you? " what was he specifically asking?

I believe that what he was specifically asking was why the airmen served in the war, even though the armed forces were racially segregated. 
Powell is important in history in that he was the first African American to serve on the joint Chiefs of staff. He was the 65th United States secretary of state, serving under the U.S president George W. Bush from 2001 to 2005, the first African American to serve in that position.