Last night Bill Moyers interviewed Senator Barbara Boxer (D-CA) on the Bill Moyers Journal. The segment covers the 20th anniversary of James Hansen's initial warning about climate change in 1988, Boxer's conflicts with Senator James Inhofe (R-OK), and the recent demise of the Lieberman-Warner Climate Security Act.
Unfortunately PBS does not make it possible to embed its videos, so you will have follow the link to the PBS website to watch it.