I generally agree.
This bit I see differently, though only with ~ 30% confidence.
> vast majority of the companies in the S&P 500 have nothing to do with defense, shipping or natural resources.
If you were evaluating the impact that a road has, and you looked at all the vehicles that passed over it every day, most of the vehicles you see would be in other industries — retail, industrial, commercial, domestic — very few of them are professional bitumen pourers who make roads. So clearly bitumen pouring only affects a low percentage of the city.
Separately, your first paragraph also seems problematic. Let’s take Vietnam and Cambodia as examples: neither has a US military base, port, nor sells natural resources to “Wall St”.
Finally, I’m not sure I follow how that would cause the US to accumulate 50% of the world’s market cap—especially because the vast majority of the companies in the S&P 500 have nothing to do with defense, shipping or natural resources. I haven’t done the math, but I would venture to guess that >50% of the S&P 500 market cap is tech or tech-adjacent.
I decry this misplaced pessimism.