What was a long-lasting result of Henry Clay's "American System"?

A creation of a more national and unfied trading economy.

Henry Clay’s "American System" remains to be one of the most significant examples of a program sponsored by the government. Through the "American system," harmony and balance in the nation’s agriculture, commerce, and industry is preserved. This type of system reinforces tariff to protect and promote American industry, national bank to nurture commerce, and state subsidies to promote the improvement of roads, canals, and etc.