Earlier quoted context omitted.
> It's said that no bank (even the best-managed) can withstand a fullscale bank run I keep reading this but this should not be true Any bank will hit liquidity issues on a full-on bank run, as not 100% of a banks assets will be marketable, but central banks will provide emergency liquidity in these situations But banks should not hit insolvency issues like SVB did
The line is a little blurry. You can be underwater in mark-to-market terms on a bond portfolio, but be fine if you guess the timeline for redemption and can hold them to maturity. Banks estimate what percentage of their assets will be held to maturity. So needing extra liquidity causes insolvency.
the PV of a bond is the risk adjusted, discounted (at current rates) FV of the bond (and interim coupons). The losses are real, they don't magically come back, they just magically appear to realign like your ETA does as you get close to your destination after losing hours in a traffic jam.