The Congressional Budget Office’s latest long-term forecast, released last month, is a bracing report. As President Obama’s term comes to end, CBO finds that the federal government is on track to run up historically large deficits over the coming three decades, pushing federal debt to 141% of GDP, up from 39% in 2008.

The president has mostly avoided talking about the federal budget during his time in office, but he did promise that the Affordable Care Act — ObamaCare — would help lower deficits in the short and long term. CBO backed him up on this claim in 2010, estimating that the deficit would be reduced by 0.5% to 1.0% of GDP over the medium term. But the agency’s new forecast shows why the law is more likely to make the deficit worse, not better.

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