political systems (such as democracy) are about power.
Precisely. Democracy allows the competition of governing ideas. Granting legitimacy to the winner (to became government) and making system stable.
I see idea of democracy in detecting power shifts without open conflicts. How many fighters would this party have if civil war erupted? Election will show. Number of votes may be very far from actual power (e.g. military strength) but it still can make the weaker side to not seek conflict anymore.
Without being explicit about what power ems will have, specifically in the meatworld, the question seems too ill-defined to me
Well, I am not even sure about powers of individual humans today. But I am sure that counting adult = 1 vote, adolescent = 0 votes is not precise. On the other hand, it does not need to be precise. Every form of power can be roughly transformed to "ability to campaign for more votes". Making votes more sophisticated would add a subgoal of "increasing voting power" that could become as taxing as actual conflict. Or not, I really have no idea; sociology is difficult.
Back on topic. I see problems when ems are more varied in personal power, compared to children vs adults variance of today. Would "voting weight" have do be more fine-grained? Would this weight be measured in a friendly competition, akin to sports of today? Or would there be privileged caste, and everyone else would have no voting rights? Would the voting rights be not granted for persons, but for military platforms instead? (Those platforms would not be actually used, they will exist just for signalling purposes.) Or will any simpleton barely managing digital signature be a voter? Subject to brain-washing by those with actual power?
I hope that these low-quality questions can help someone else to give high-quality answers.
But I want to stress that I do not see any problems specific to copy-ability of ems. Democracy only measures power of political party, democracy does not reflect on which methods have lead to the said power.
One person, one vote - a fundamental principle of our democratic government. But what happens in a world where one person can be copied, again and again?
That is the world described by Robin Hanson's "Em economics". Ems, or uploads, are human minds instantiated inside software, and hence can be copied as needed. But what is the fate of democratic government in such a world of copies? Can it be preserved? Should it be preserved? How much of it should be preserved? Those are the questions we'll be analysing at the FHI, but we first wanted to turn to Less Wrong to see the ideas and comments you might have on this. Original thoughts especially welcome!
To start the conversation, here are some of the features of idealised democracy (the list isn't meant to be exhaustive or restrictive, or necessarily true about real world democracies). Which of these could exist in an Em world, and which should?
EDIT: For clarification purposes, I am not claiming that democracies achieve these goals, or that these are all desirable. They are just ideas to start thinking about.