Jim, you raised a lot of issues that kind of requires a longer reply, so I wrote a new article. A bit longer than I had anticipated: https://erik-engheim.medium.com/is-the-norwegian-oil-fund-a-socialist-idea-bed4a20d7982
But the short version is that I cannot agree with your characterization.
The US states with major access to oil are typically conservatives and ideologically wedded to capitalism. Yet none of these are being prudent about balancing budgets and saving money. Hence I dont' see how this is a democrat problem. The US as a country cannot control oil production as that is the domain of the individual states.
Also I cannot say I have ever seen conservative politicians advocate that surplus revenue should be saved. The normal conservative response to excess government income is to cut taxes.
Keep in mind that Norway despite massive oil revenue has kept very high taxes. There are no instances I can remember where conservatives have retained high taxes while having access to massive oil revenue. No, they will usually splurge that oil money on tax cuts.
Norwegian social programs are primarily funded by taxes, so no different than the US. The oil revenue has primarily been saved. Only in later years have spending been padded with a lot of money from the oil fund.
I also don't think the Norwegian approach can be characterized as capitalist at all. This kind of major involvement by government in the economy goes completely against the beliefs of most people who are ardent champions of capitalism.
These massive oil incomes the Norwegian state has gotten exist due to very active government involvement in the economy:
1. Ultra high taxes. 80% taxes on oil. Contrast that with the 1% Oklahoma conservatives set on oil taxes. Could the contrast be any starker?
2. Government owned oil company to extract even more profits.
3. Forcing private oil companies to recover twice as much oil from a well than they would have wanted themselves. American conservatives would protest against that as overregulation and government overreach.
The latter has made it possible for Norway to strech its oil supply much longer, and profit over more years.
The heavy government involvement in Norway in the economy is far beyound what any American democrat would have dared suggest. Barack Obama e.g. after the 2008 economic crash refused to nationalize American banks.
That is exactly what all Nordic social democracies did in the same situation.
Obama was it was politically impossible to do in the US. In the US there is an an extreme paranoia about Government owenership of business. Imagine the US government taking over all major banks in 2008? It would have cause mass hysteria and screams of "socialist revolution."
In Norway and Sweden this was just business as usual. It meant our bankers didn't get fat bonus for speculating like crazy. Instead reckless shareholder losts their money. Instead the Government made money selling banks back later to the private sector. In the US in contrast the government lost a lot of money while the private sector which had been reckless made a ton of money on bailouts.