William McKinley was a popular president. He led the nation during the emergence of the United States into its modern position as a global economic and military power.

Businesses did well, jobs were abundant, and the booming economy grew even stronger as the United States became more heavily involved in international trade. During McKinley's presidency, the United States quickly and decisively won the Spanish-American War (1898).

Debate continues, however, about McKinley's effectiveness as president. He intended to address several key issues during his second term. But his opportunity was cut short with his assassination in 1901.

Throughout his political career—as a congressman, as governor of Ohio, and as president—McKinley promoted business interests. Taking a cautious approach, he supported the protection of American business and industry by taxing imported goods to keep their prices high. He preferred to allow home businesses to manufacture and sell...