Hi Duncan, Greg: I think the “problem” with democracy as unsuccessfully fostered by the USA and colonial European powers is that it had to serve THEIR needs - for oil, bananas, gold, whatever. So, they were perfectly ready to support elites with a sheen of democracy (see:Afghanistan). Those elites robbed the nations blind.
In fact, I recall an unpopular WB study that showed developing democracies where rival elites competed for control were often more corrupt than authoritarian regimes - because authoritarians wanted the system to work, while they siphoned off the wealth. But when a democratic faction took power, their elites grabbed all they could, because they knew their time in power was limited.
All this to say - democracy works best when, duh, the people want it and it, and not so well when it is imposed.