The 21st century is in danger of becoming an era of statue smashing and historical erasure. Not since the iconoclasts of the Byzantine Empire or the epidemic of statue destruction during the French Revolution has the world seen anything like the current war on the past. In 2001, the primeval Taliban blew up two ancient Buddha statues in Afghanistan on grounds that their very existence was sacrilegious to Islam. In 2015, ISIS militants entered a museum in Mosul, Iraq, and destroyed ancient, pre-Islamic statues and idols. Their mute crime? These artifacts predated the prophet Muhammad. The West prides itself in...