Budget experts have watched the federal government’s budget process fail over the last few years as the policy choices required to put the budget on a sustainable path grew more challenging. The darkening long-term outlook, masked by investors’ willingness so far to lend to the U.S. government at low rates, could at any time be greatly complicated by rising interest rates, or by unpredictable but inevitable future economic or other emergencies demanding higher spending. The publicly held federal debt is racing past 70 percent of the nation’s gross domestic product (GDP) and is projected to grow even more rapidly in coming decades, driven by the long-forecast retirement of the baby boomers and continuously rising healthcare costs—two of the biggest factors in what fiscal commission co-chair Erskine Bowles calls, “the most predictable economic crisis in U.S. history.”