The Federal Deposit Insurance Corporation (FDIC) resolved 490 unviable banks, using resources from its deposit insurance fund financed by all the banks. The US Treasury provided recapitalisation support and guarantees through its Troubled Asset Relief Program (TARP). The Federal Reserve undertook a thorough stress-test, determining banks’ additional capital needs.
To understand the situation we are in in Europe, it is useful to make a thought-experiment, and imagine that no such federal institutions exist in the US. Imagine that the state of California would have had to come up with the TARP money for Wells Fargo instead of the US Treasury.