This week, in honor of the G.O.P. Convention, In The Past Lane explores the fascinating history of the Republican Party. I speak with historian Heather Cox Richardson, author of a superb history of the Republican party. She’ll take us on a fascinating journey through eras when the GOP was the party of big business and Wall Street and when it periodically shifted to become the party of the people and the common good. And she'll bring her analysis all the way to the present to help put Donald Trump in historical perspective.