War is hell, but it also sells ... some of which may otherwise have lain around gathering dust on studio back lots. 'Hollywood is a very conservative industry,' says Colin Kennedy, deputy editor ...

Tracing the evolution of the war-film genre from 1898 to 1996 by combining real-life combat footage with excerpts from Hollywood movies. Clips range from "Wings" (1927) to "Courage Under Fire" (1996).