The banks are too big to fail. We have a technology so called the "Printing Press". When the force of deflation do come, all the Central Bank need to is to make $100,000,000,000,000.00 out of thin air by simply clicking a mouse button and hope it would solve the problem with massive inflation.
In the event that there is a bank failure and all deposits were guaranteed, that $20,000 wouldn't have worth the original purchasing power of $20,000 one had initially deposited due to the eroding power of inflation.
That's my opinion anyway by observing what the global central banks have been doing lately to "solve" the credit crisis.