Which two men were leaders behind the American system?

The two men most prominently associated with the American System were Henry Clay and John C. Calhoun. Henry Clay, a prominent politician and speaker of the House, advocated for a comprehensive economic plan that included protective tariffs, a national bank, and internal improvements such as roads and canals. John C. Calhoun, initially a supporter of the American System, played a significant role in promoting its principles, particularly in the context of regional development and infrastructure. Their combined efforts aimed to unify the nation's economy and promote national growth.