What is "american system"

The term American System can mean one of the following:

• American system of manufacturing, for a system of manufacturing developed in America.
• American System (economic plan), for the program of Henry Clay and the Whig Party.
• American School (economics), for the Hamiltonian American School of which the American System (economic plan) is a part.
• United States customary units, a system of measurement used in the United States

The American System was an economic plan that played a prominent role in American policy during the first half of the 19th century. Rooted in the " American School" ideas of Alexander Hamilton, the plan "consisted of three mutually reinforcing parts: a tariff to protect and promote American industry; a national bank to foster commerce; and federal subsidies for roads, canals, and other ' internal improvements' to develop profitable markets for agriculture." Congressman Henry Clay was the plan's foremost proponent and the first to refer to it as the “American System”.