James Naughtie continues his look at the ideas tying America's founding to the modern United States, as he looks at what it means to be an American.

In Chicago, he joins the Columbus Day parade - an exuberant celebration of Italian-American identity - and hears about the Great Migration of African Americans from the South to northern cities like Chicago. In Wisconsin, he visits the birthplace of the Republican Party, and in Ohio the Governor shows him the spot where Abraham Lincoln heard he had been formally confirmed as President-Elect. James considers how the social movements of the 1960s moved the centre of gravity of American politics from economic to social issues, with all that meant for political polarisation.

Producer: Giles Edwards