Is there a philosophical justification for democracy? It seems that it would have to be an argument from self-interest, but if we ask, "Whose self-interest?" then it would seem that a democracy isn't the best form of government for certain minority groups (e.g., a theocracy might be more in line with the interests of religious fundamentalists). And what if democracies are even downright harmful to, e.g., the elite?
Also, a somewhat related question: is there a philosophical justification for taking from the rich and giving to the poor (which it seems is what socialism prescribes)? This question is 'somewhat related' to the previous question in that even if a democracy does benefit all, it certainly deprives certain groups of advantages they might otherwise have, and so, given a history, it cannot actually benefit all equally.