Imagine a U.S. president on a camping trip It seems unlikely today, but in May 1903, President Theodore Roosevelt dismissed his Secret Service men to go camping with John Muir, the world-famous naturalist. For three glorious nights and four days in California's Yosemite National Park, the two men talked about birds, giant sequoia trees, glaciers, as well as the importance of preserving wilderness for future generations. They slept under...