At the midpoint of Donald Trump’s first term, historians have struggled to detect the kind of virtues that offset his predecessors’ vices: the infectious optimism of Reagan; the inspirational rhetoric of JFK; the legislative smarts of LBJ; or the governing pragmatism of Nixon. So rather than being viewed as the reincarnation of Ronald Reagan or Franklin Delano Roosevelt, Trump gets cast as a modern-day James Buchanan, Franklin Pierce or William Harrison.