The Landesbanken have long been a pillar of German financial security and they will be just as valuable in America. They are banks that are publicly owned by the government and therefore do not have the incentive to gamble with their customers money for the sole purpose of their own profit. They have been essential to allowing small businesses the same loans and rates as the large corporations, and have been a staple of Germanys recovery. These features and diverse others would make public banking incredibly valuable to incentivize innovation and competition in the public sector. In addition it would force the private banks to cater much more to the needs of the customer in order to compete.
For more information:
http://www.alternet.org/economy/15273