As Percy Shelley knew when he wrote Ozymandias, the iconic is defined by the iconoclastic. In its brazen or marmoreal defiance of mortality every civic statue to this or that  ‘King of Kings’ already has encoded into it its own death as a negative potentiality waiting to be fulfilled. Those who made history through destruction are already constructing the process which will make them in their turn colossal wrecks. As Shelley knew too, passion and mockery are perpetual. I vote that Edward Colston gets winched out back on to the  Bristol dock. But every year he gets dunked again, in a new exuberant  ritual as regular as the seasonal tides and annual currents of ocean voyages.