Has the regulation of banks has been a failure.

In the sense that there were huge gaps in the regulation: yes. These gaps allowed the banks to make stupid business decisions which they are now paying for. And the taxpayers are helping them pay for it. It also allowed them to take advantage of their customers.

In the sense that without regulation they would have behaved in a more asinine manner and abused their customers even more: no.

Unfortunately, I do not believe there is a cure for that. Watching the congressional hearings, it seems obvious to me that the legislators (both parties) are more interested in posturing than legislating constructive changes. There also seemed to be a noticeable lack of knowledge and understanding of the issues among some of them.