Image copyright Getty Images Image caption Buchanan was a notable right-wing presence on a left-leading network

MSNBC, a cable news channel with a leftish slant has parted company with Pat Buchanan, the veteran conservative who ran for president in 2000 on a third party ticket and tried for the Republican nomination twice before that.

He had been a commentator on MSNBC for a decade.

The channel says he has been fired because of views expressed in his book, Suicide of a Super Power, which contains chapters on "The End of White America" and "The Death of Christian America".

On his blog, Pat Buchanan says he has fallen victim to blacklisters. He says he does think homosexuality is unnatural, but implicitly denies he is racist.

I haven't read the book, but judging from extracts it is easy to see how his pungently expressed anti-multiculturalism could be seen as racist.

But I do know the sort of views he is expressing are shared by many American conservatives who think their culture is under attack (just look at the comments on his blog, if you don't believe me).

It probably isn't good for democracy if these people feel their views can't be expressed in public.

But this isn't really about censorship or about fear on the right of a huge liberal conspiracy in the media.

Conservative views that seem very far to the right by British standards are all over the place - from blogs, to right-wing talk radio, and above all on Fox News.

Trapped in the box

You can't be in America long before you hear people bemoan the death of a more bipartisan past.

To an extent this is piety, but sometimes the split in the media makes America feel like it is dividing into two armed camps.

There is a grave danger for American democracy that the two parties not only can't agree, they can't even discuss.

Left and right live in their little ghettos of the mind, unwilling to listen to anything that doesn't reinforce their own views. If you only hear what your opponents are thinking through the warp of second-hand caricatures, then there is no chance of understanding their point of view.

Thinking gets trapped within a very narrow box - one that often bears little relation to problems in the real world.

It would be sad if the silencing of a maverick has made this worse. It is always better for both your mental and political health to throw things at your TV or radio, than nod sagely as it confirms your prejudices.