Red states. Blue waves. These are phrases we hear all the time these days. Political correspondent Steve Kornacki says this is nothing new.He says it was the '90s that have brought us today's polarized politics. In his new book, The Red and the Blue: The 1990s and the Birth of Political Tribalism, Kornacki traces the origin story back several decades.Want to support 1A? Give to your local public radio station and subscribe to our podcast. Have questions? Find us on Twitter @1a.