This article talks about the story behind Jasper Johns painting Flag.
Norman Rockwell's the Four Freedoms is a series that refers to Franklin D. Roosevelt's speech in 1941 addressing our essential human rights. These paintings inspired patriotism across America and resulted in selling millions in U.S. Treasury Department War Bonds in 1943.
American Impressionist Childe Hassam painted The Fourth of July, 1916 in response to his attendance at the a parade in New York that was part of a collection of patriotic activities planned as American prepared to enter World War I.
Jacob Lawrence created his War Series depicting various aspects of war inspired by his own experiences serving in the United States Coast Guard during World War II.