Polarization is not new to this country. It is hard to imagine a society more divided than ours was in 1800, when pro-British, pro-commerce New Englanders supported John Adams for the presidency while pro-French, pro-agriculture Southerners backed Thomas Jefferson. One sign of this hostility was the passage of the Alien and Sedition Acts in 1798; another was that in 1800, just as in 2000, an extremely close election was settled by a struggle in one state (New York in 1800, Florida in 2000).
The fierce contest between Abraham Lincoln and George McClellan in 1864 signaled another national division, this one over the conduct of the Civil War. But thereafter, until recently, the nation ceased to be polarized in that sense.
James Q. Wilson