Democratic opposed Henry Clay's American System because they believed that it was unconstitutional since it gave the government too large a role in the economy.
The American system program was intended to promote economic development and diversification, reduce dependence on imports, and tie together the different sections of the country.However, the American System became the chief plank in the platform of Clay’s Whig party, which was formed in opposition to the Democratic party of Andrew Jackson, creating ‘the second party system.’ Whigs were found in all parts of the country, but especially among the prosperous classes, in areas wanting government economic aid, and among Protestant religious bodies that hoped a strong government would further their agenda of moral reform.