The core problem of focusing on institutions not activities:
The theory behind so-called systemically important financial institutions, or SIFIs, is fundamentally flawed. Financial crises are pathologies of an entire system, not of a few key firms. Reducing the likelihood of another panic requires treating the system as a whole, which will provide greater safety than having the government micromanage a number of private companies.A crisis is a run:
The risks to a system are most pronounced when financial institutions borrow heavily to finance investments. If the value of the assets falls or becomes highly uncertain, creditors—who include depositors—will rush to pull out their money. The institution fails when it is unable to find a new source of funds to meet these obligations.