The Fed (the reserve and the FDIC) in addition to The Office of the Comptroller of the Currency regulate banking practices. If banks are failing then it's the lack of proper regulation that's responsible.

Regulation is not to designed to prevent every failure. Banks are private, not owned by the state, as the U.S. is a capitalist system.

Regulation should exist to limit or eliminate the risk of Americans having to pay to cover for bad executive decision making. The whole point of laws and regulations are to protect people and their interests. It is in the public interest to have a stable banking system, and it's also in the public interest to not have to pay premiums for deposit insurance (which we all currently do)

Because actions of fed made the bank unstable. By lowering value of things it hold

And then other people attacked it causing a bank run that put it over the edge.

Without the run, it likely could still be operating without too big issues.

The bank chose to make risky investments with the deposits it held. That's on the bank, not the fed.

US Treasuries?