For a man who grew up to become the "Bull Moose", Theodore Roosevelt was a sickly child, suffering from asthma and other maladies. But his physical weakness actually drove him to be more active, which also fostered an interest in nature. It also helped that Teddy's family was wealthy, allowing him privileges including home school and the ability to attend Harvard, where he was an athlete and took an interest in naval affairs. After finishing at Harvard, Teddy entered politics, but it didn't stop him from writing The Naval War of 1812 in 1882, establishing himself as a professional writer and historian.
In the 1890s, it was Teddy's turn to make history, leading the Rough Riders during the Spanish-American War and being decorated for his service with a Medal of Honor. He parlayed his glory into the governorship of New York and then the Vice Presidency under William McKinley. When McKinley was assassinated in 1901, young Teddy was thrust into the presidency, one that would earn him a place on Mount Rushmore, Roosevelt's "Square Deal" domestic policies favored average citizens while busting trusts and monopolies. Roosevelt also promoted conservation as an environmental stance, while his "speak softly and carry a big stick" foreign policy is still an oft used phrase today. Roosevelt even earned a Nobel Prize during his presidency.
Franklin Delano Roosevelt might be America's greatest 20th century president, but there's no question that he was the most unique. A well-connected relative of Theodore Roosevelt, FDR was groomed for greatness until he was struck down by polio. Nevertheless, he persevered, rising through New York politics to reach the White House just as the country faced its greatest challenge since the Civil War, beginning his presidency with one of the most iconic lines ever spoken during an inaugural address.
For over a decade, President Roosevelt threw everything he had at the Great Depression, and then threw everything the country had at the Axis powers during World War II. Ultimately, he succumbed to illness in the middle of his fourth term, just before the Allies won the war.
Among America's presidents, Harry Truman's presidency produced some of the nation's most crucial decisions and left one of the nation's most unique legacies. When President Franklin Roosevelt died in April 1945, Vice President Truman, somewhat unprepared for the Presidency, now had to fill some of the biggest shoes in American history. Incredibly, Truman had not been informed of the country's secret attempt to build atomic bombs, confiding in his diary after learning about it, "We have discovered the most terrible bomb in the history of the world. It may be the fire destruction prophesied in the Euphrates Valley Era, after Noah and his fabulous Ark."
The new president had to usher America through victory in Europe in his first month and decide to drop atomic bombs on Hiroshima and Nagasaki a few months later, but the end of World War II produced only the first of many consequential decisions Truman would face during his nearly 8 years in office. As president, Truman would lay the groundwork for the next 50 years of American foreign policy, as the architect of Cold War containment, the man who signed off on the Marshall Plan, and the commander-in-chief during much of the Korean War. He would also be the president who finally integrated the military, a crucial step on the way to full civil rights for the country's minorities.