That sound you hear is the ice cracking.

All around us.

With economic activity contracting in 2009's first quarter at the same rate as in 2008's fourth quarter, a nasty U-shaped recession could turn into a more severe L-shaped near-depression (or stag-deflation). The scale and speed of synchronized global economic contraction is really unprecedented (at least since the Great Depression), with a free fall of GDP, income, consumption, industrial production, employment, exports, imports, residential investment and, more ominously, capital expenditures around the world. And now many emerging-market economies are on the verge of a fully fledged financial crisis, starting with emerging Europe.

Fiscal and monetary stimulus is becoming more aggressive in the U.S. and China, and less so in the euro zone and Japan, where policymakers are frozen and behind the curve. But such stimulus is unlikely to lead to a sustained economic recovery. Monetary easing--even unorthodox--is like pushing on a string when (1) the problems of the economy are of insolvency/credit rather than just illiquidity; (2) there is a global glut of capacity (housing, autos and consumer durables and massive excess capacity, because of years of overinvestment by China, Asia and other emerging markets), while strapped firms and households don't react to lower interest rates, as it takes years to work out this glut; (3) deflation keeps real policy rates high and rising while nominal policy rates are close to zero; and (4) high yield spreads are still 2,000 basis points relative to safe Treasuries in spite of zero policy rates.

Fiscal policy in the U.S. and China also has its limits. Of the $800 billion of the U.S. fiscal stimulus, only $200 billion will be spent in 2009, with most of it being backloaded to 2010 and later. And of this $200 billion, half is tax cuts that will be mostly saved rather than spent, as households are worried about jobs and paying their credit card and mortgage bills. (Of last year's $100 billion tax cut, only 30% was spent and the rest saved.)