Federal Reserve is the ultimate backer NOT the US government. That's one of the key functions of the central bank. All they will do is make more Treasury purchases, build up reserves and extend special loans to the member banks. Provide liquidity, so to speak. Some banks will be allowed to fail, but almost all large key banks are members of the system so they will always have liquidity. Take a look at DRL, their refinancing came from the large member banks. This is a non-member bank that was basically bailed out. PPT is a function of the Federal Reseve as well.
That bank that failed had 15 million in deposits. thats less than at least 1/2 of the ET posters that regularly waste their valuable time here, have in their Murial Seibert accounts.