There are two broad views on our newly resurgent global bubbles--the increase in asset prices in emerging markets, fuelled by capital inflows, with all the associated bells and whistles (including dollar depreciation). These run-ups in stock market values and real estate prices are either benign or the beginnings of a major new malignancy.

The benign view, implicit in Secretary Geithner’s position at the G20 meeting last weekend, is most clearly articulated by Frederic (Ric) Mishkin, former member of the Fed’s Board of Governors and author of "The Next Great Globalization: How Disadvantaged Nations Can Harness Their Financial Systems To Get Rich," in the Financial Times this morning.

The UK's top financial regulator, Adair Turner, has suggested a tax on all financial transactions around the world. The purpose of this tax, he argues, would be to prevent the return of "business as usual" for the banking sector: "If you want to stop excessive pay in a swollen financial sector you have to reduce the size of that sector or apply special taxes to its pre-remuneration profit."