It's not every day we receive advice in our business from a U.S. President, past or present, living or dead. Theodore Roosevelt (popularly referred to by historians as "TR") is thought of as a superb manager as president and in other chapters of his career: politics, events, departments, and especially people. So reports OmegaHRSolutions.
One school of revisionist history holds that, had TR been president or a member of the diplomatic corps in the run-up to World War I, the "Great War" might very well have been avoided. We'll never know that for sure, but his record as a judge of talent, along with the standards he set for hiring/firing and performance evaluation helped usher in the very concept of "hiring manager" to 20th-century America. Much of his methodology and ideas regarding personnel management continue to hold true, 100-plus years after the fact.