As to libertarians, certainly in a world with no deposit insurance or government guarantees I could argue against government interference in the structure of private banks. But banks are not private in this country. They are quasi-public institutions (and if you read Niall Ferguson you might conclude that large banks have always been quasi-public institutions). There is a synergy between big banks and big government. Jefferson and Jackson were right. So breaking up big banks fits in with breaking up big government. Which is why we won't see the Progressive elite breaking up big banks.