There’s been no more reliable regurgitator of fantastical Trump-Russia collusion theories than Democratic Rep. Adam Schiff. So when the House Intelligence Committee chairman sits down to describe a “new phase” of the Trump investigation, pay attention. These are the fever swamps into which we will descend after Robert Mueller’s probe.

The collusionists need a “new phase” as signs grow that the special counsel won’t help realize their reveries of a Donald Trump takedown. They had said Mr. Mueller would provide all the answers....