If you are referring to the Vietnam War, there were several different artists involved in displaying their disagreement with US involvement in this war. This includes the works of Billy Joel, Marvin Gaye, and Pete Seeger.
These artists used their lyrics to accomplish several different goals. Billy Joel's "Goodnight Saigon" paints a picture of what it is like to be a US soldier training for Vietnam and living/fighting in Vietnam. The artists also used rhetorical questions in hopes of bringing attention to what actions we are taking right now. This is a strategy used by Marvin Gaye in his song "Whats going on."
The expansion of imperialists was assisted by missionaries that were sent ahead of colonizers to spread Christianity, the religion of the Empire. In doing so, they also spread Western ideals and the English language. The path made by religious scouts made imperialism, easier.
