Robert J. Samuelson: If we can't kill farm subsidies, what can we kill?

Despite a deficit obsession, Americans still seem ill-informed about the magnitude of the gaps. A recent CBO report is illuminating. Even with a full economic recovery, current policies imply annual deficits over the next decade averaging 5 percent of the economy (gross domestic product); by 2022, federal debt to GDP would hit 90 percent (the 2007 figure: 36 percent).

Balancing the budget in 2020 would require $1 trillion of spending cuts or tax increases. The recent "fiscal cliff" agreement hardly alters these forecasts because it closes only about 8 percent of the next decade's projected deficits, estimates the Committee for a Responsible Federal Budget.

Government needs reappraisal. Programs shouldn't be immortal in the face of changing economic and social conditions. What's no longer justified should be discarded.

Unfortunately, President Obama has evaded and discouraged this discipline. Republicans emphasize spending control but are often hypocritical on specifics. Politics favors the status quo; economics calls for change. Farm subsidies are but one example.

As the CBO observes: "Very few policy changes, taken individually, can shrink the deficit [sharply]. ... Significant deficit reduction is likely to require a combination of policies, many of which may stand in stark contrast to policies now in place."

Still, agriculture would be a good starting point. In 2013, Congress will continue debating a farm bill. It would be refreshing, if surprising, to see subsidies phased out because — whatever their historical justification — they're no longer needed.

Robert J. Samuelson is a Washington Post columnist.