No exit from Fannie and Freddie?

It was a year ago this week that the federal government seized ailing mortgage-finance giants Fannie Mae (FNM) and Freddie Mac (FRE). Their collapse, it was feared, could imperil the entire financial system. The takeover wasn't meant to be permanent, but a new congressional report illustrates why it may be especially challenging to undo.

The reason? Privatizing Fannie and Freddie "credibly" will be exceptionally difficult because investors will probably expect that the government will simply swoop in again with another bailout should the companies run into trouble later, according to an assessment by the Government Accountability Office (PDF).