Whether you think we should trim the deficit right now or not, this paragraph from the CBO on Options for Reducing the Deficit gives a stark picture of the underlying issue. Most striking to me is that most of us probably don’t even know what it is and we’re certainly not talking about it.
Under current law, spending for all federal activities other than the major health care programs and Social Security is projected to account for its smallest share of GDP in more than 70 years. At the same time revenues would represent a larger percentage of GDP in the future—averaging 18.3 percent of GDP over the 2014–2023 period—than they generally have in the past few decades. Despite those trends, revenues would not keep pace with outlays under current law because the government’s major health care programs and Social Security would absorb a much larger share of the economy’s output in the future than they have in the past.