In only a generation or two we could be right back to fuedalism !
No, it's a self-balancing stable system. The more tax breaks and subsidies you give yourself, the smaller your vote. Do remember that the poor will naturally outnumber the rich to a great degree, and that the reverse is impossible. Giving a bit more power to the productive (less stupid) people would lead to political debate being a bit more intellectual.
Our current system is unstable. Welfare slowly increases over time because the poor are able to vote for it. They destroy their own jobs (their global competitiveness) via all sorts of goodies that raise the cost of employing them.