I think most of the Chinese debt is actually internal, whereas most of the US debt is external?

China is also a large external creditor, for example holding a large amount of treasury bonds from other countries.

I certainly don't know how either of those impact the calculus of which is worse and/or more manageable though.

US debt is also mostly internal. 2/3 of all US bonds are held by US citizens or companies. Of the foreign holders of US bonds, Japan holds the most.

Almost all of US debt is internal. Social security and the federal reserve are the two biggest holders. Only 25% is in other countries, and the largest single other country is Japan at 3%.

If there is a secret Trump plan to devalue the dollar and force us treasury holders to accept cheaper longer term debt, the biggest plenary will be to social security.

One visualization:

https://www.visualcapitalist.com/charted-heres-who-owns-u-s-...

(Though on the last numbers I saw had the UK and China with far more similar amounts of holdings.$

Calling T-bills debt is only half the picture. They function more like dollars, whose value can be deflated or increased after issuance merely by changing interest rates.

Great info. I imagine most of that 20% of Intra-Governmental Debt is Social Security and Medicare/Medicaid?