talk radio-- conservative; MSM-- liberal....ok, but why?

Why is talk radio dominated by conservatives? Is it a function of those who drive in their cars? Is it a reaction to other media dominated by liberals (e.g., network TV and especially newspapers)? There's probably some good explanation, but the stories I can weave sound somewhere between good and contrived to fit the data.

Thoughts?

Anyway, that thought echoed in my mind again-- as I perused an interview by James Taranto with Andrew Breitbart in the WSJ-- on the occasion of his role in the ACORN videos. I didn't follow the ACORN blow-out closely, so the details of this are quite interesting-- as well as the tension in covering the news ethically.

James O'Keefe, the 25-year-old aspiring filmmaker who played the pimp in the Acorn meetings, came to Mr. Breitbart in early August with his videos. They showed Mr. O'Keefe and his putative partner in crime, 20-year-old Hannah Giles, asking Acorn counselors for advice on how to evade the authorities while setting up a business offering the sexual services of underage girls smuggled into the U.S. from El Salvador. It was a shocking and outlandish tale, but employees in at least five Acorn offices fell for it and offered to help.

"I had a 20-year-old and a 25-year-old and my integrity on the line if we were going to launch this," Mr. Breitbart says. "It was so obvious that the mainstream media, given this information, would not cover it and would, in effect, attempt to cover it up." So he devised an intricate strategy of rolling out the videos one at a time, anticipating Acorn's defenses and rebutting each in turn with the next video...

Mr. Breitbart's work on the story has centered on a sophisticated public-relations campaign. He placed exclusives not only with Fox, but with local newspapers in the cities where the videos were made. On his site, he published the raw videos and complete transcripts, lest he and Mr. O'Keefe be accused of manipulation through editing.

The crux of the strategy was the timing of the video releases....

Yet some caveats are in order. Partisanship was not the only reason for media resistance to the Acorn story. The approach Mr. O'Keefe and Ms. Giles used—lying to prospective sources or subjects—is grossly unethical by the standards of institutional journalism. Almost all major news organizations, including the Journal, strictly prohibit it. To be sure, there is a world of difference between employing such tactics and reporting on the results when others have used them. And there is no question that the pair's findings were newsworthy. But journalistic discomfort with their methods is a sign of integrity, not corruption....