> in 2026 I cannot imagine why they are continuing to, except inertia.

Because there is no where else for that debt to go. No one else wants to take on so much debt.

Meanwhile there are a bunch of asset managers who are paying the mortgage on their beach home in the Caribbean with the bonuses they earn by investing in US debt. If the US defaults on that debt 10 tears from now that means they still earned 9 years of million dollar salaries, and anyways they won’t be blamed for something the entire industry suffered from at that point.

If they do the prudent thing and ask for a higher price they will end up investing fewer dollars which reduces their 2% commission on invested capital, money that might go to their international equity golfing buddy instead.

Entities where the money is managed by the investor itself (for example, foreign national governments) do indeed appear to be cutting back.

Because everyone has a lot of dollars and they need to earn a return, so its either the Eurodollar market or US debt. US debt is safer. But its true to say that people are more and more reluctant to buy longer dated bonds and are turning to shorter and shorter maturities which is another problem for the US government.

The UK itself lost one third of its land area in 1921, following yet another insurrection in Ireland (always a coerced part of the UK subject to genocidal rule and expropriation).

The last straw for the Irish was summary executions of the insurrectionists and the ravages of the Black and Tans -- like ICE but with arsonists and criminals, but without masks. The US will be fortunate if the parallels remain only financial.

The individual dynasties, however, lasted about 250 years each, like the others listed. China also got taken over by the Mongols in the mid-1200s, (retaken by Han Chinese a century later), and then by the Manchurians in the mid-1600s. Chinese civilization, not just the government, got taken over by European rationalism/modernism in 1940s with the Communist Revolution. (It's ironic that the Chinese government talks complains about "Western influences", when their whole governmental ideology is based on European ideas.)