How is it that undemocratic leaders—who exploit, imprison and brutalize their subjects—frequently maintain power for far longer periods than their democratic counterparts? Autocrats, the authors argue, need only reward only a small class of loyalists—the army, judiciary, an inner circle of advisers—who will reliably suppress opposition. While democrats likewise dispense rewards—sweetheart contracts, farm subsidies, welfare payments—they are constrained by a system of government that requires the loyalty of fickle voters. This ensures that if a leader accumulates wealth and power in a few hands, his job security weakens.

Wasn't all this written down half a century ago by naughty Nick? Bueno de Mesquita and Smith summarize their rules for dictators (as part of a series for The Monkey Cage) and apply them to Qaddafi: