That is the topic of my latest Bloomberg column. Here is one excerpt:
…historians stress the importance of contingency, that things really could have gone another way. The decisions of a solitary assassin or the outcome of a single battle can shift the course of history. Particular leadership decisions might have avoided or limited World War I. Or what if the Germans had not, in 1917, put Lenin on a train back into Russia? The Bolshevik Revolution might have been avoided and probably the entire course of history would have been different. A shrewder President Paul von Hindenburg might have prevented the rise of Adolf Hitler.
If you think about these questions enough, you can end up very nervous indeed. Historians have seen too many modest mistakes spiral out of control and turn into disasters.
Economists, in contrast, work more with general models than with concrete historical situations, and those models emphasize underlying structural forces. Economies have fairly set populations, birth rates, natural resources, capital stocks, savings rates, trading partners, and so on. So to an economist, the final outcomes are closer to necessary than contingent…
And when it comes to politics, economists of the “public choice” variety tend to see outcomes as controlled by a fairly tight structure of voter preferences and interest groups, variables which a president can change only at the margin and with great effort.
So which perspective is correct — the historian’s or the economist’s?
There is much more at the link, including a discussion of how Paul Krugman’s strong anti-Trump stance fits into this picture.