For most of its 75-year history, the program had paid its own way through a dedicated stream of payroll taxes, even generating huge surpluses for the past two decades. But in 2010, under the strain of a recession that caused tax revenue to plummet, the cost of benefits outstripped tax collections for the first time since the early 1980s.

Now, Social Security is sucking money out of the Treasury. This year, it will add a projected $46 billion to the nation’s budget problems, according to projections by system trustees. Replacing cash lost to a one-year payroll tax holiday will require an additional $105 billion. If the payroll tax break is expanded next year, as President Obama has proposed, Social Security will need an extra $267 billion to pay promised benefits…

Social Security is hardly the biggest drain on the budget. But unless Congress acts, its finances will continue to deteriorate as the rising tide of baby boomers begins claiming benefits. The $2.6 trillion Social Security trust fund will provide little relief. The government has borrowed every cent and now must raise taxes, cut spending or borrow more heavily from outside investors to keep benefit checks flowing.

Many Democrats have largely chosen to ignore the shortfall, insisting the program is flush, citing the existence of the trust fund. They argue that fixing Social Security can wait, perhaps for years.