The National Air and Space Museum has an exhibit that is worth a few minutes of your time. Called Artist Soldiers: Artistic Expression in the First World War, it displays art from two different perspectives. One is that of professional illustrators recruited by the military, and the other is by soldiers who created stone carvings in underground shelters.
Until World War I, war art largely consisted of romanticized battles or heroic military leaders. But these WWI works show soldiers at war in a realistic way. I’ve included a few pictures to give you a sense of the exhibit.