There were so many instant internet spoofs making fun of Kellyanne Conway’s now-famous “Bowling Green Massacre” that it’s hard to pick a favorite. Gun to my head, I’d say mine was the Twitter meme that showed a brass plaque dedicated to the names of the poor souls left for dead on Bowling Green’s grassy killing field. It was blank.

That’s because there was no massacre there. No one died. No one even stubbed a toe. But there’s a good chance you know that by now: that the supposed terrorist attack in Bowling Green, Ky., that Ms. Conway, a top presidential adviser, invoked on MSNBC last week to justify President Trump’s contentious travel ban never happened. (And, no, the reason you had never heard of it was not because the Dishonest Media ignored the alleged carnage at the time of its non-happening, as Ms. Conway alleged.)

The very fact that you probably know all this means that the “Bowling Green Massacre” may go down in the record of the Trump presidency as the first break in the “fake news” clouds that have cast such gloom over our fair and once (relatively) true republic.

The same internet that enabled false stories to run unchecked through news feeds during the election year dispatched new white blood cells that attacked Ms. Conway’s “alternate facts” with “true facts” (a redundant term that I guess we’re stuck with for now). Their most effective attack was traditional reporting, in many cases from news organizations that have doubled down on fact-checking, joined by newfangled memes that accentuate the truth.