Theodore Roosevelt

The great conservationist president. Roosevelt protected some 230 million acres of public land, using the Antiquities Act to set aside the Grand Canyon and many other sites, and helped seed the idea that became the National Park Service in 1916. Standing at the Grand Canyon he urged Americans to "leave it as it is… the ages have been at work on it, and man can only mar it."

He also mediated the end of the Russo-Japanese War largely by telegraph from Sagamore Hill, New York — never actually traveling to Portsmouth during the negotiations, meeting delegates only before and after at his own estate. The resulting Treaty of Portsmouth won him the 1906 Nobel Peace Prize, the first awarded to an American.