Community, Mega, and Goldilocks Banks in U.S. History

Three types of banks, community (small, relationship-based), mega (very large, transaction-based), and goldilocks (middling, mix of relationship and transaction-based) are surveyed throughout U.S. banking history. Megabanks are relatively new and while they pose threats to macroeconomic stability they are not strictly necessary for economic growth. Economies of scale have been found in some recent studies but they appear to include underpriced government insurance and rewards for bad behavior (profits > penalties). Regulators should encourage community and, especially, goldilocks banks by reducing/eliminating subsidies to megabanks