I read the following from one of my favorite economists, David Friedman, this evening:

Is there any reason why the solution to the problems of the corporation – the takeover bid – does not solve the problems of democratic government? Yes. The difference between the two cases is that your “share” in the US is not transferable property – which may be why, if casual observation is to be trusted, democratic governments are worse run than most corporations.

Your share in the US is not transferable property – but perhaps it could be. Imagine that it were. Each citizen owns one citizenship, which includes one vote. You may leave the country and sell your citizenship to someone who wants to live here. If the country is badly run, someone can buy up a vast number of citizenships, elect a competent government, and make a fortune reselling the citizenships at a higher price. The country need not be emptied while the operation is going on; the operator can always rent his citizenships out between the time he buys them and the time he sells them.