The answer is what it has always been: limit the power of government.

We tried that when we founded this country, but the human urge to accumulate power eventually routed around the systems they put in place to ensure those limits.

Unfortunately, this is a hard sell. Although most people hate the idea of the government making them do things they don't want to, they also really like the idea of eventually harnessing that power for their own ends. Soros recognized the agency problem, but also advocates a powerful centralized authority controlling the world's monetary system (among other things).

On top of that, the election system we have now selects for candidates who want power. Real libertarians are hard to come by, and the kind of person who believes in "live and let live" is also the kind who wouldn't touch politics with a ten-foot pole.

I wish I had an easy answer. Term limits would help, and in the past I have broached the idea (only partly in jest) of drafting political leaders from an eligible population like jury duty.