Rockwell Paintings at the Smithsonian American Art Museum

IN an age when Democrats and Republicans are barely on speaking terms, you might not think that decades-old paintings of freckled schoolboys and their loyal mutts could help revive the conversation about what we value as a nation. Yet Norman Rockwell’s cheerful America has lately acquired a startling relevance both inside and outside the art world, in part because it symbolizes an era when connectivity did not require a USB cable.

Rockwell’s paintings are easy to recognize. In the years surrounding World War II his covers for The Saturday Evening Post depicted America as a small-town utopia where people are consistently decent and possess great reserves of fellow-feeling. Doctors spend time with patients whether or not they have health insurance. Students cherish their teachers and remember their birthdays. Citizens at town hall meetings stand up and speak their mind without getting booed or shouted down by gun-toting rageaholics.

This is America before the fall, or at least before searing divisions in our government and general population shattered any semblance of national solidarity. Rockwell’s scenes of the small and the local speak to us in the age of the global because they offer a fantasy of civic togetherness that today seems increasingly remote. “To me the most important part of Rockwell’s work is that it illustrates compassion and caring about other people,” the filmmaker George Lucas, who lives in Marin County, Calif., said recently. “You could almost say he was a Buddhist painter.”...