Imagine a world where an artist is considered an essential worker. The government commissions murals and sculptures for schools, libraries, and hospitals. Taxes fund free classes in pottery and printmaking at a community art center. The president of the United States promotes art as vital to a healthy democracy. This world flickered into view between 1933 and 1943, a decade when the US government treated art as a public resource rather than a private luxury. The output was staggering: hundreds of thousands of artworks—murals, paintings, sculptures, prints, and photographs—by then-unknown artists like Willem de Kooning, Philip Guston, Lee Krasner, Jacob Lawrence, Alice Neel, Louise Nevelson, Isamu Noguchi, Jackson Pollock, and Mark Rothko. They belonged to the era’s bold vision of cultural democracy: art by the people, for the people. This vision rose from a nightmare: the Great Depression. By the time Franklin D. Roosevelt took office in March 1933, three and a half years after...