He doesn't want to have to redeem those $1.7 trillion in bonds in the Trust Fund.
See also Krugman's latest:
http://www.nytimes.com/2005/01/11/opinion/11krugman.html?oref=login&n=Top%2fOpinion%2fEditorials%20and%20Op%2dEd%2fOp%2dEd%2fColumnists%2fPaul%20KrugmanThe Iceberg ComethBy PAUL KRUGMAN
Published: January 11, 2005
Last week someone leaked a memo written by Peter Wehner, an aide to Karl Rove, about how to sell Social Security privatization. The public, says Mr. Wehner, must be convinced that "the current system is heading for an iceberg."
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