> BTW, state-owned factories almost always failed (numerous examples in 20th century Europe).

Industrial factories, yes. Local utilities seem to do well enough in Europe.

I wonder if there's a principled difference?

Quite a lot of private factories have failed in the west too. Factories are very vulnerable to globalisation.

Utilities, on the other hand, are a natural monopoly inherently tied to a geographic location. They're not producing a "product", but instead a commodity that's the same for all customers. Many utilities are mostly forms of "road" - they just happen to be wire-shaped or pipe-shaped roads.

Note the mostly. Telecoms and electricity have two parts: the central, complex, services; and the big mostly-dumb network.

well Telecoms networks can be quiet complex and in the USA broadly you had more complexity at the local plant level than say the UK does.

Its the last mile that makes telcos's natural monopoly's not the exchanges/switches/central offices

Like the electricity/internet provider in my city of Jönköping, Sweden. It is a for-profit company, owned by the municipality.

The Municipality obviously dictates the goals, like 100/100 fiber in the most remote parts of the area (which I just signed up for), and the company gets to execute them in the way it sees fit.

The municipality housing company is operated the same way.

I wonder about the state owned investment funds and if there is a parallel to state owned factories. Norway has a giant sovereign wealth fund built off of its oil industry, but does it perform as well as a private fund would? What about the California pension funds. I understand that they get screwed by their private equity and hedge investments all the time. I wonder if they weren't public funds if they would have more clout on wall street and could work out better deals to get better returns.