Randall W. Forsyth subbing for Alan Abelson at Barron's Up and Down Wall Street has the answer.
Warning: Trilateralists, Illuminati and Transnational Conspiracy ahead.
A (bearish) hedge-fund operator, in a letter to his investors, describes how a senior Wall Street marketing director recounted the genesis of the current situation:
"'Real money' (U.S. insurance companies, pension funds, etc.) accounts had stopped purchasing mezzanine tranches of U.S. Subprime debt in late 2003 and [Wall Street] needed a mechanism that could enable them to 'mark up' these loans, package them opaquely, and EXPORT THE NEWLY PACKAGED RISK TO UNWITTING BUYERS IN ASIA AND CENTRAL EUROPE!!!!
"He told me with a straight face that these CDOs were the only way to get rid of the riskiest tranches of subprime debt. Interestingly enough, these buyers (mainland Chinese banks, the Chinese Government, Taiwanese banks, Korean banks, German banks, French banks, U.K. banks) possess the 'excess' pools of liquidity around the globe. These pools are basically derived from two sources: 1) massive trade surpluses with the U.S. in U.S. dollars, 2) petrodollar recyclers. These two pools of excess capital are U.S. dollar-denominated and have had a virtually insatiable demand for U.S. dollar-denominated debt...MORE