I thought the way Heinlein postulated in his book "Starship Troopers" was interesting..
There were 2 levels of citizenship - One by birth, and a higher level you earned by military or Govt service - the higher level entitled you to vote, and hold government office, among other things..
That meant, he said, that the people who determined who that gov't was, were the same people who understood what the government did and didn't do, and knew the value of "good" government...
Neat premise, but it'd never fly.
Jamie