A Miami-based investment management firm, one of the largest junior preferred shareholders of Fannie Mae and Freddie Mac, this week offered to buy and operate the MBS guaranty businesses of the two government-sponsored enterprises with $52 billion of private capital and “a business plan that is sustainable with or without a federal reinsurance plan.” In a four-page letter to Federal Housing Finance Agency Acting Director Edward DeMarco, Bruce Berkowitz, chief investment officer of Fairholme Capital Management, proposed to form two new state-regulated insurance companies to own and operate the assets of Fannie and Freddie “that are relevant to the continuing insurance business.” Under the Fairholme plan, the new MBS guarantors would be capitalized...