WASHINGTON -- In recent weeks I had become increasingly glum about the prospects for Social Security reform this year (although I think in the long run the pro-reform movement will prevail). Thus, I couldn't get too excited by the release of Senator Jim DeMint's new plan. But I have to reconsider. The basics of DeMint's plan are that it only uses the Social Security surplus to create personal accounts and it initially only puts treasury bonds in those accounts. In early 2008 an advisory board similar to the one that manages the Thrift Savings Plan will start adding other investment...