Most news consumers understand that media, in general, plays favorites. They cheer on and protect Designated Heroes, and with seemingly boundless energy relish every opportunity to assail Designated Villains. We’ve long known, from polling and other quantifiable metrics, that journalists have very pronounced political biases. Even as journalists often indignantly tout the objectivity of their work product and defend the credibility of others in their profession, the sorry results stand for themselves. It’s no longer controversial—other than in the most surreal, eye-rolling conversations with committed left-wing partisans—to say the American media leans overwhelmingly left and has a strong preference for...