Nouriel Roubini writes:

The massive volatility and sharp equity-price correction now hitting global financial markets signal that most advanced economies are on the brink of a double-dip recession. A financial and economic crisis caused by too much private-sector debt and leverage led to a massive re-leveraging of the public sector in order to prevent Great Depression 2.0. But the subsequent recovery has been anemic and sub-par in most advanced economies given painful deleveraging.

Now a combination of high oil and commodity prices, turmoil in the Middle East, Japan’s earthquake and tsunami, eurozone debt crises, and America’s fiscal problems (and now its rating downgrade) have led to a massive increase in risk aversion. Economically, the United States, the eurozone, the United Kingdom, and Japan are all idling. Even fast-growing emerging markets (China, emerging Asia, and Latin America), and export-oriented economies that rely on these markets (Germany and resource-rich Australia), are experiencing sharp slowdowns.

Until last year, policymakers could always produce a new rabbit from their hat to reflate asset prices and trigger economic recovery. Fiscal stimulus, near-zero interest rates, two rounds of “quantitative easing,” ring-fencing of bad debt, and trillions of dollars in bailouts and liquidity provision for banks and financial institutions: officials tried them all. Now they have run out of rabbits.