Indeed, the bankers themselves sought the alliance for they found it impossible to erect voluntary cartels on the market. It would take the violence of the State to achieve that. The State, too, has an interested in controlling the money, as to expand their ability to illicitly appropriate goods, and so they're fine allowing the banking industry to share in the loot, too.
RE: Review of: Making Economic Sense, Murray Rothbard (Chapter 2)