For example, the U.S. housing boom was unsustainable because it was not possible to indefinitely keep relaxing credit underwriting standards to qualify new buyers to stoke demand. It was also unsustainable because the rise in prices often led to a supply response that limited the prospect of further price increases. 2  BIS central bankers’ speeches  Another class of threats to financial stability emerge from sudden reversals of market sentiment regarding economic policy and institutional arrangements. This is a complex issue which I will not explore in detail today, other than to note that here too, early profits all too often feed pro-cyclical behavior, undermining market discipline. This in turn facilitates the accumulation of both private and public imbalances that are painfully difficult to unwind when financing suddenly stops. When sudden reversals occur, large costs are imposed on the real economy and the financial system, costs that are not fully internalized by the market participants that may have benefited from the boom. The often significant negative externalities associated with financial market instability suggest that regulation and prudential standards should be aimed both at limiting the frequency and extent of booms and at building a more resilient financial system, so there is less damage when the busts inevitably occur. The goal here is not to use regulation to prevent or even limit innovation, whether real or financial. Many innovations have generated significant benefits for the macro-economy. For example, the Internet, which lay at the heart of the tech bubble, generated myriad benefits.

In many areas, we have identified the necessary tasks only in general terms. Progress in figuring out the details and the implementation path and how to coordinate the efforts on a cross-border basis is more limited. I would particularly highlight the cross-border coordination problem – regulatory oversight is national, but many financial firms and infrastructures operate on a global basis. Effective reform requires mutually consistent global standards – and while international cooperation to date has been good on many fronts, progress is uneven, and the devil is in the details of implementation. We need all national authorities to resist the temptation to favor domestic financial interests over the interest of achieving a true level playing field globally. And we should resist the urge to favor locally controlled infrastructures where global solutions would better advance the collective financial stability interest. Instead we should work to ensure fair access to global infrastructures. Also, it is important that national regulators have access to data and a role in the regulatory oversight of such global infrastructures when that is relevant to their own national financial stability agendas. In the United States, I think we have made more progress in bolstering the resilience of our banking institutions than we have on the other tracks. There are two elements to this. The first element is the increase in capital that has already occurred. The major U.S. banking institutions are much better capitalized today than they were in the fall of 2008.