We might not be here if the mainstream media, which loved the Steele Dossier when it seemed to incriminate Donald Trump, had later shown an equal interest in investigating its origins as a partisan fabrication. In his now-famous transcript, Mr. Trump mainly presses Ukraine’s new president for dirt not on the Bidens but on the known unknowns of 2016. “I would like you to find out what happened with this whole situation with Ukraine,” he says. “There are a lot of things that went on, the whole situation.” This is the “favor” he actually seeks from Ukraine’s president. Yes, Mr....