Can the world be made safe for the return of securitizations? That is a question of great importance to those like John C. Dugan, the comptroller of the currency, who say they believe that the banking system on its own is unlikely to have the ability to provide enough credit to sustain an economic recovery in the United States. “We need a vibrant, credible securitization market to help fund the real economy going forward,” Mr. Dugan said this week. He was preaching to the choir — a meeting of the American Securitization Forum — but it is an opinion widely held in financial markets.