All this matters even more urgently when you consider the McCabe firing as a road-test for Trump’s method in an impending showdown with Robert Mueller.

What will the president’s party in Congress permit? What will the president’s media supporters repeat? What will the president’s supporters in the country believe? The story they have been told about McCabe previews the story they will soon hear about Mueller.

As many have noted, Trump’s March 17 tweet about Mueller—his first to attack Mueller by name—heaps lie upon lie.