My main point is that I see high concentration of wealth as a danger to a representative democratic system.

Fair enough. I'll just try to nudge you on one point.

I don't see a substantive difference between private or governmental players when it comes to the will or ability to cause great harm.

In my farmers and cobblers fable, all human interaction is voluntary, based on mutually beneficial exchange. No one gets hurt by other people.

In the real world, "no system is perfect" as you say and crime will be a problem to deal with. But consider some of the foulest of history's great harms:

• World War II - 40 to 70 million souls lost

• World War I - 15 to 65 million

• Great Leap Forward - 15 to 55 million

• Japanese Conquest - 5 to 30 million

• Russian Civil War - 5 to 9 million

• Bengal famine - 4 million

• Napoleonic Wars - 3.5 to 7 million

• Holodomor and Soviet Famine - 2.5 to 8 million

• Second Congo War - 2.5 to 5.4 million

• Cambodian Genocide - 1 to 3 million

These events are a sample of the worst anthropogenic disasters which were unambiguously prosecuted by government, and therefore legal. There's an argument that some of these, most obviously WWII, were horrific but could have been even worse without government intervention. But most of these were due to adventurism, conquest, and social experimentation in which the death and suffering of others was an accepted part of the plan.

Slavery is the only horror I can think of that compares, but even when it was commonly accepted by governments and practiced widely it did not claim anything like the hundred million victims in the above list.