Hector St. John Crèvecoeur’s Letters from an American Farmer: popularized the idea of the United States as a melting pot of ethnicities. was a thinly disguised allegory explaining the need for the Constitution. made the author so unpopular in the United States that he was forced to return to France. argued that America should reject manufacturing and remain an agrarian nation. made the case that free African-Americans were ""citizens of color"" deserving of full legal rights.