A new book entitled How the Other Half Banks by Mehrsa Baradaran makes a great argument for why we need a postal banking system. The book explains how economic inequality in this country is caused largely by unequal credit. A significant portion of the population has been deserted by the banking system and is consequently forced to use payday lenders and check-cashing services to cover emergency expenses and pay for necessities. The best solution to the problem, argues Baradaran, is postal banking.

Baradaran has written previously about why the U.S. Postal Service should get back into the banking business in the Harvard Law Review and the New York Times.

"The post office has branches in many low-income neighborhoods that have long been deserted by commercial banks," writes Baradaran in her NYT piece. "And people at every level of society have a certain familiarity and comfort in the post office that they do not have in more formal banking institutions."

(Order the book on Amazon and have the Postal Service deliver it.)