Economic plan to help expansion and economics.
An economic plan based on ideas of Alexander Hamilton, and headed by Henry Clay, consisting of a high tariff to support internal improvements such as road-building (expansion west), and a national bank to encourage productive enterprise and form a currency. This program was intended to allow the United States to grow and prosper, by providing a defense against cheap foreign products, mainly at the time from the British Empire. Promoted by Whigs in 1830's.
Important because this plan was to help the US expand especially westward, as well as depend less on foreign goods and more on internal products which thus pissed the South off and made the West/North happy.