The U.S. government will purchase preferred shares of Freddie Mac and Fannie Mae in an effort to boost confidence in the mortgage finance giants, U.S. officials announced today. Treasury Secretary Henry Paulson says the actions were being taken because "Fannie Mae and Freddie Mac are so large and so interwoven in our financial system that a failure of either of them would cause great turmoil in our financial markets here at home and around the globe."