It’s hard to say who is the worst attorney general in American history. The candidates are many and comprise a veritable rogue’s gallery of sadists, reactionaries and incompetents. They range from A. Mitchell Palmer, mastermind of the original Red Scare that decimated the left in the wake of the First World War, to Jefferson Beauregard Sessions III and William Pelham Barr, who sacrificed the rule of law in service to Donald Trump. Merrick Garland may not share the malignancies of his fellow train wrecks, but he deserves to be in the discussion. Decades from now, historians will memorialize Garland not...