The problem with this approach is that, throughout much of human history, autocratic states did not face off against democratic competitors. Autocracies can certainly do well against other autocracies, but to return to political science jargon, these rivalries do not provide variation on the independent variable. A study of why the Mongols were able to overthrow China’s Jin dynasty would be interesting, but since they are both autocracies, it would not tell us anything about how democracies and autocracies stack up against one another, which is the focus of this book.
