Children who study our era a century from now will watch the videos we all saw of the Capitol attack, the unleashed barbarity of it, the mob searching for the politicians President Trump blamed most for his demise, starting with Mike Pence, the former vice-president, and Speaker Nancy Pelosi. “Hang Pence,” they chanted. “Where’s Nancy?” For the lead attackers, this was an assassination attempt. And they came closer than we had dared to imagine. Democratic prosecutors showed that Trump has blood on his hands, that he urged them on, that he let them rampage for hours without lifting a finger, an…