Pat Buchanan is no longer a contributer at MSNBC, in large part because of the large amount of outrage at his racism, a kind of racism that is not far from that lurking in the background of Ron Paul. Buchanan was an at-will hire, he has the freedom to be free from government intervention in his freedom to speak and write what he believes. And his employer has the right to discontinue his employment when those views are extreme and offensive, as they did in his case.
I wrote about the background of racism and anti-semitism of Pat Buchanan here, for readers not familiar with Buchanan's history.
Here is the text of the petition that was responsible - at least in part - for getting Buchanan canned: