Ross Douthat doesn't think Democrats should be shutting out the network that's setting the trend for the future:
boycotting Fox means boycotting the future. Media outlets of all stripes, I suspect, are only going to grow more opinionated/biased over the next few decades, which means that more and more viewers who aren't partisans will, by default if not by choice, end up getting their news from anchors and writers who are. Which means, in turn, that if you boycott a network because it's hostile to your party, you'll be effectively boycotting a host of viewers who aren't.
Douthat is arguing that we need to passively accept this inevitable future and perhaps even embrace it as desirable. After all, he attempted a defense of ABC after they conducted their little show trial two weeks ago, so it would seem that he's all in favor of allowing news to decline into Fox's unique blend of mindlessly partisan and unprincipled conservative propaganda and tabloid news.
As to whether Democrats should go on Fox, I don't think the "they need to prove they can debate the opposition" argument is really relevant. Are Fox viewers the really sort looking for an honest debate to help them make up their mind about choosing presidential candidates? Are a significant number of them going to vote for a Democrat? It seems that when Democrats do go on Fox, they say things they hope will appeal to conservatives, but which end up alienating liberals. Since they're not likely to pick up conservative voters by appearing on Fox, shouldn't they take a page from Bill Clinton and fight back against smears and lies?
--Mori Dinauer