Just like I think he is over playing how much of this simply coming from the right. Cable news is part of the problem but the real extremism comes from talk radio (both sides) and the internet. Many of these fairly well known websites have become virtual hate groups. Look at the comments you see at places like red meat or Kos. These people only talk to people like themselves and work themselves into a frenzy convincing themselves that the other side is not only wrong with ideas but that they have evil intent.

I think part of the answer is we need to stop giving the fringe so much voice. Obama may be in part a victim but I think he also needs to take a large share of the blame. Part of his strategy has been to make the republicans appear as a dead end group of extremist who only know how to say no. That is why he call Rush a party leader and why his staff draws so much attention to groups like the birthers. For all of Bush's faults he didn't waste time and give credibility to the truthers. Attacking and insulting dissenters is also not an effective method of bring down the tone in this country. If the left has problem with the tone these days they really should look at what comes out of their own mouths and ask how that is affecting tone.

The biggest role I think the media is playing in the escalating levels of partisanship in this country is that they lost the faith of the American people. Polls show that Americans trust the media about as much as they trust the politicians they cover. Grossly biased coverage from places like the NYT is a major factor in that loss of trust.