The substantial increase in federal support of the single-family housing finance system, as well as weaknesses uncovered in the wake of the mortgage market meltdown, have led to a U.S. finance system that warrants reform, according to the Government Accountability Office. The GAO focused considerable attention on the much-reported fact that government programs have accounted for a huge share of the mortgage and MBS market since the financial crisis. The congressional watchdog views the federal role in housing finance as a “high-risk area.” “Developments in mortgage markets since 2000 have challenged...