JOSEPH SOHM is an American history teacher turned photo-historian. Over 30 years, he has photographed the 50 states and published his images more than 50,000 times in such publications as National Geographic, The New York Times, The Washington Post, and Wall Street Journal.. Sohm’s images are featured in Frederick J. Ryan’s portrait of Ronald Reagan, The Great Communicator; and in Al Gore’s Oscar-winning film An Inconvenient Truth.