If you buy a T-Bond at 110 the treasury will pay you back 100 at maturity, thus you lost money in nominal terms (depending on coupon rate). This has been happening in Europe with their previously negative yielding debt

What you mean to say is there's no credit risk. Not the same thing as you can't lose money. Saying you are guaranteed X dollars 30 years from now does not mean much at all if people need money today. This is not "safe" or prudent

Yes, but you would get more than that if you bought an (equally safe) treasury bond today. So it doesn’t make sense to claim that your bond is “still worth $5”.

Also, $5 today is not the same currency as $5 in ten years.

No, you’re fundamentally misunderstanding that a bank needs to be able to pay people when they withdraw their money. You can’t sell a bond that will be worth $5 in 30 years to get $5 in cash now when people can buy them from the fed for $3.

This has nothing to do with America, this is you not understanding duration risk.

Right, but the bank didn't invest 100% of its funds in MBS and t-bills; IIUC they had plenty to manage their projected operations cost and regular withdrawal / deposit activity. What changed is the panic / bank run. The panic sank them, but it'd sink basically any bank because no bank keeps enough liquid assets to clear all its deposit obligations.

... so SVB not only didn't have cash, it didn't have assets people were willing to buy / loan against to cover enough withdrawals to stop the run even though those assets had guaranteed ROI, which is interesting to me. Not enough lenders / potential creditors think some 10-year T-bills (and bailing out one of the biggest banks in the country on the lender's terms) is worth it?

Interesting.