At the start of this year, I owned a lot of T-bills. But, not being American, I don't lend money to the US anymore.
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What institutions do you trust if the US defaults on the debt? Where?

Sorry, I didn't mean to imply that I think there is much default risk visible to me for US government securities, especially for Americans. I'm not particularly worried about a US default. Everything has risks, and those aren't big in the grand scheme of things. As mentioned, the US can never be in a financial situation that they are unable to redeem US dollar denominated bonds, so any default would be purely intentional.

No, I just prefer not to invest much in the US any more because it is now a declared enemy of the West. Siding with Russia and North Korea against erstwhile allies and announcing plans to forcibly annex bits of Latin America, Europe and Canada puts me into the same situation as a Ukrainian considering investing in Russia: fine if you're cool with that sort of thing, but not for me, thanks. So long as there are alternatives, I'll look to those. Some people comment that "it will never happen", but if you're a citizen of one of the countries involved, that dismissal is indescribably offensive. And naïve.

I certainly appreciate that many Americans don't agree with Washington's stance on all such matters, and that's valid and (to some like me) appreciated, in the same sense that I appreciate that there are lots of really nice peaceful folks in Russia. But I also appreciate that neither group's views matter a whit. One deals with the world as it is, not as one wishes it to be.

Jim