Here's a great John Piper sermon, dating back to the beginning of the Clinton presidency. Amazingly little has changed in the situation between then and now. You'll see what I mean. The message is on How to Be Pro-Life Christians Under a Pro-Choice President. I generally love Piper's political perspectives, because of his great respect for the God-given role of government, and the human beings God raises up to fill those roles. This message is no exception.