All eyes were on Wall Street Monday morning as Freddie Mac, one of the two giant government-sponsored enterprises that dominate U.S. mortgage finance, floated $3 billion in bonds to continue its role as a buyer and reseller of mortgage obligations. The bond sale came after a week in which Freddie’s stock, and the stock of its sister Fannie Mae, plummeted as analysts and economists worried that the housing bubble collapse would push the two GSEs into insolvency. To fortify Fannie and Freddie, the Bush Treasury Department, with blessings from the Democratic Congress, worked feverishly over the weekend to cobble together a bailout plan should the GSEs’ conditions worsen to the point that they can no longer function. The successful bond sale indicates the Bush plan has reassured the market — albeit barely.

It is an article of faith across the political spectrum that Freddie and Fannie cannot be allowed to fail — especially not at this time when the broader housing market is undergoing painful correction. Why do they have such exalted status?

Before Fannie Mae — the first of the twins — was created amidst the “Recession within the Depression” in 1938, home mortgage lending was highly risky for banks. State regulation kept banks small and geographically limited in order to make them better targets for taxation and political manipulation. As a result, banks could not geographically diversify their loan risk, leaving them highly vulnerable to localized economic downturns. Because they lent money (as mortgages and business loans to farms and other firms) to local borrowers for long periods of time but they had to honor local depositors’ withdrawal requests, banks were often one bad harvest and one bank run away from insolvency. For that reason, they shied away from financing long-term home loans.

Fannie Mae (formally, the Federal National Mortgage Association) provided badly needed lubricant to the mortgage industry. It purchased loan obligations from banks, putting money back in the banks’ vaults and making that money available for more home loans. Fannie financed its operations by borrowing on Wall Street and, later, by pioneering the creation and sale of mortgage-back securities (MBSs) — selling large “bundles” of loans to investors and then servicing the loans on the investors’ behalf. In this way, Fannie diversified loan risk, allowing a nationwide (and worldwide) pool of investors to finance (at first indirectly, then directly) a nationwide pool of mortgages. This wasn’t the ideal solution that banking reform would have been, but Fannie was a good second-best solution.

Because of its tax-free status and government backing (as well as banking regulations that constrained would-be competitors), Fannie quickly came to dominate the mortgage industry. This system hummed along, unchanged, until 1968 when Fannie’s costs conflicted with Lyndon Johnson’s efforts to rein in the federal budget amidst the war in Vietnam and the war on poverty. It was decided that Fannie would be spun off as a private corporation whose investors would bear its costs. However, Fannie retained its tax-free status and received a $2.25 billion line of credit at the U.S. Treasury. It also was allowed to operate with much lower reserve requirements than banks. But the most valuable of Fannie’s parting gifts was its implicit too-big-to-fail status: because of its history and role in mortgage lending, investors believe the federal government will ride to Fannie’s aid if it ever became financially unable to function. For this reason, investors buy Fannie’s stocks, bonds, and MBSs.

Congress realized that, with those perks and its original dominant position, Fannie would continue to monopolize the U.S. home loan market. In 1970 they created Freddie Mac (formally, the Federal Home Loan Mortgage Corporation) as a competitor, with the same structure and perks as Fannie. It’s unclear why Congress believed a duopoly was better than a monopoly. (For more on Fannie and Freddie’s history, listen to Peter Van Doren’s recent podcast.)

Over the last decade, analysts have offered numerous criticisms of Fannie and Freddie’s dominance and nature, and issued calls for reform. (In Regulation alone, see: Van Order 2000, Frame & White 2004, Wallison 2004, Jaffe 2006.) Besides the GSEs’ dominance of the market and the risk that their too-big-to-fail status poses to taxpayers, the implied guarantee encouraged the GSEs to retain possession of some of their mortgages instead of selling them to investors. Retaining mortgages and reaping the payments enriched Fannie and Freddie shareholders, but it subjected the two GSEs to interest rate risk as well as the default risk of all Fannie- and Freddie-guaranteed loans.

Despite the criticisms and reform calls, the issue gained little traction, even in the go-go real estate market of the mid-2000s when Freddie and Fannie were involved in a relatively small 40% of new home loans. The result is that, in the aftermath of the housing bubble collapse when preserving mortgage financing is incredibly important, the market for those loans is dominated by two teetering giants.

Fannie and Freddie are currently involved in roughly half of all U.S. mortgages. That includes a large majority of post-bubble mortgages, as private investors have pulled back from financing non-guaranteed loans. Given that position and the overall turmoil in the housing market, the federal government cannot leave Fannie and Freddie to struggle — after all, their debt equals the debt of all other U.S. corporations combined, and imagine what would happen if all U.S. corporations suddenly defaulted on their loan payments.

So, there seems little that federal policymakers can do now except promise to prop up Freddie and Fannie if they become insolvent and hope that doesn’t occur. But this situation demonstrates why the mortgage industry should not be dominated by two firms — especially two government-sponsored firms.

If Congress does adopt legislation to protect Fannie and Freddie, that legislation should spare taxpayers and the nation from a repeat of the current crisis. The legislation should include an ironclad commitment to make Fannie and Freddie fully independent of the government over the next decade. It should also require that the GSEs be broken into several smaller firms that aren’t too big to fail. Those firms would be put under strict government oversight and conservative risk controls until they are fully independent. The legislation should also strip Fannie and Freddie of their tax-free status, putting them on equal footing with private lenders (including banks, which can now geographically diversify following the 1999 banking reform). With this reform implemented, the mortgage market would become supported by numerous institutions (some of which would be Freddie and Fannie spin-offs, others not) instead of just two vulnerable pillars.

It is because policymakers refused to reform state banking regulation in the 1930s that Fannie (and later Freddie) were created. It is because Fannie and Freddie were not reformed in the last 10 years that we’re stuck with this problem now. Federal policymakers cannot disregard another opportunity at reform — or else the U.S. mortgage industry will remain at the mercy of the financial health of two firms.

Postscript (7/15): Cato senior fellow Gerald O’Driscoll sketches a plan for breaking up Fannie and Freddie and making them truly independent in this excellent WSJ op-ed [$].