If you are interested in history and politics, this excellent radio interview provides historical context to the church-state divide, so seemingly precarious today. Garry Wills is an exceptional knowledgeable thinker/writer. he tell of how the English monarch encouraged tolerance while the settlers in Massachusetts were executing heretics. (in the 17th century) I knew of the latter but not the former. It's also hopeful that, in the future, as in the past, there'll be a backlash.
Enjoy. Interview link also includes book excerpt from Head and Heart: American Christianities. Important history to understand to fight Republican Evangelical ahistorical ignorant Christians.