...If the nation has a father of bank insurance, it is Joshua Forman, one of the promoters of the Erie Canal. Early in the 19th century, New York State had a string of bank failures, and Martin Van Buren, then governor, asked him to restructure the banking industry. Forman’s insight was that banks were vulnerable to chain-reaction panics. As he put it — in a line unearthed by the Harvard Business School historian David Moss — “banks constitute a system, being peculiarly sensitive to one another’s operations, and not a mere aggregate of free agents.”

In 1829, Forman proposed an insurance fund capitalized by mandatory contributions from the state’s banks. Debate in the State Assembly was heated. Critics said failures could overwhelm the fund; they also argued that its very existence would reduce the “public scrutiny and watchfulness” that restrained bankers from reckless lending. This remains the intellectual argument against insurance today. But Forman’s plan was enacted, and subsequently five other states adopted plans.

All did not go smoothly. In the 1840s, during a national depression, 11 banks in New York State failed and the insurance fund — as prophesied — was threatened with insolvency. The state sold bonds to bail it out....