What we initially conceived as a fairly simple geologic experiment on Mars ultimately turned into humanity's first real overland expedition across another planet. Spirit explored just as we would have, seeing a distant hill, climbing it, and showing us the vista from the summit. And she did it in a way that allowed everyone on Earth to be part of the adventure.
Democratic leaders, whose power is ultimately dependent on popular support, are held accountable for failing to improve the lives of their citizens. Therefore, they have a powerful incentive to keep their societies peaceful and prosperous.