As Tory hopefuls bid to become prime minister, they might like to reflect on Cyrus the Great (r. 557-530 bc), who created the first Persian empire, stretching from the Mediterranean to Pakistan. The soldier-essayist Xenophon (d. 354 bc) spent eight books explaining why he was the model Supreme Leader. The Romans were wildly enthusiastic about it, as were Milton, Gibbon and Machiavelli.