The fact that so many of Hopper's paintings make good postcards and prints makes the worry about cliché even stronger. His most famous painting, "Nighthawks", the one with the people sitting in a diner late at night, has become global kitsch. Everyone has seen the version with James Dean and Marilyn Monroe, or the thousand and one different puns and knock-offs that resonate throughout popular culture. The accessibility and near-universal appeal of that painting, like so much of Hopper, starts to make a person suspicious. The common denominator of such work must be pretty low if the painting works in a video game or on a TV show without even missing a beat.