Foreign Affairs has an article by Columbia professor Charles Calomiris and Stanford Professor Stephen Haber on banking regulation:
In this new American Game of Bank Bargains, populism continued to play a central role in determining the allocation of credit and profit. However, by the late twentieth century, the center of populist power had shifted from rural areas to big cities. In 1977, Congress passed the Community Reinvestment Act to ensure that banks were responsive to the needs of the communities they served. The CRA required banks that wanted to merge with or acquire other banks to demonstrate that responsiveness to federal regulators; the requirements were later strengthened by the Clinton administration, increasing the burden on banks to prove that they were good corporate citizens. This provided a source of leverage for urban activist organizations such as the Neighborhood Assistance Corporation of America, the Greenlining Institute, and the Association of Community Organizations for Reform Now, known as ACORN, which defined themselves as advocates for low-income, urban, and minority communities. Such groups could block or delay a merger by claiming that the banks were not in compliance with their responsibilities; they could also smooth the merger-approval process by publicly supporting the banks. Thus, banks seeking to become nationwide enterprises formed unlikely alliances with such organizations. In exchange for the activists' support, banks committed to transfer funds to these organizations and to make loans to borrowers identified by them. From 1992 to 2007, the loans that resulted from these arrangements totaled $850 billion. From the point of view of an ambitious banker who was seeking to create a megabank of national scope, making such loans, which represented risks that the banks might not otherwise have taken, was simply part of the cost of doing business.