Since when does a weekend gathering of “nearly 275” white nationalists in a country of more than 320 million people warrant front-page coverage in major newspapers? Since the election of Donald Trump, apparently.

The same media outlets that insisted Mr. Trump wouldn’t beat Hillary Clinton have spent the past two weeks misleading the public about why he did. Breathless coverage of a neo-Nazi sideshow in the nation’s capital—where antiracism protesters almost outnumbered attendees, according to the Washington Post—helps liberals...