With the perennial push to boost the number of women in politics, it’s worth asking whether the world would be a more peaceful place with a bigger proportion of females at the helm. The only way to go beyond the theoretical in responding to such a question is to scrutinize the records of those women who’ve ruled. Women leaders, of course, are in the minority. But experience suggests a world of women presidents and prime ministers, queens and empresses would yield a world order not dissimilar to the one we have now.