Ben Olken is an unusual, young economist, a member of Harvard’s Society of Fellows, and he’s co-written a paper, “Hit or Miss?,” about whether killing a leader actually benefits anyone. Can an assassination (as Brutus apparently believed with Julius Caesar) really restore or expand democracy? Can that single act (as John Wilkes Booth and Lee Harvey Oswald seemed to think) change the outcome of a war or an already settled political course?

The question is important (not just to JFK in Dallas, obviously) because it actually addresses Olken’s larger inquiry: Do individual leaders really matter as much as economic or political forces?