What was the source of major political debate between 1820-1850?

he pre–Civil War years (1820–1860, or the “antebellum years”) were among the most chaotic in American history—a time of significant changes that took place as the United States came of age. During these years, the nation was transformed from an underdeveloped nation of farmers and frontiersmen into an urbanized economic powerhouse. As the industrialized North and the agricultural South grew further apart, five major trends dominated American economic, social, and political life during this period.

Explanation:

the answer should be monarchy

the answer is mass marketing.