Theodore Roosevelt became president in 1901 after the assassination of William McKinley, whose vice-president he had been. He served until 1909.
Roosevelt was called a "trust-buster" and proudly wore the moniker, promoting himself as a heroic smasher of corporate monopolies. He clashed with Big Business, bullying it with regulators and antitrust law. New regulatory bodies took shape under his presidency; reforms such as child-labour restrictions and workplace-safety measures gained ground. The civil service expanded and became more professional. As the writer H.L. Mencken quipped, Roosevelt "didn't believe in democracy; he believed simply in government."
During the 1907 financial crisis, Roosevelt fell silent about the "malefactors of great wealth" he had attacked weeks earlier and let J.P. Morgan's US Steel swallow a financially distressed rival.
Motivated in part by a belief in the natural superiority of the Anglo-Saxon man, Roosevelt sent American troops overseas to expand America's influence. His reasoning became known as the "Roosevelt Corollary" to the Monroe Doctrine: that America may be forced to exercise "an international police power". He quadrupled spending on the navy, turning it into a modern force to support an empire. He fomented a rebellion in Panama against Colombian rule to take control of the nascent canal project.
His flair for diplomacy won him a Nobel peace prize for mediating an end to the Russo-Japanese war of 1905. Rarely in all this did he bother to ask Congress for permission.
Before his presidency, Roosevelt was made a hero by the Spanish-American War of 1898. He led the Rough Riders, a cavalry unit made up of cattle ranchers, coppers and polo players, which helped drive Spain out of Cuba and Puerto Rico within months.
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