To criticisms, Obama supporters make two arguments. First, the CBO says the plan reduces the deficit by $143 billion over a decade. Second, the legislation contains measures (an expert panel to curb Medicare spending, emphasis on “comparative effectiveness research”) to control health spending. These rejoinders are self-serving and unconvincing.

Suppose the CBO estimate is correct. So? The $143 billion saving is about 1 percent of the projected $12.7 trillion deficit from 2009 to 2020. If the administration has $1 trillion or so of spending cuts and tax increases over a decade, all these monies should first cover existing deficits — not finance new spending. Obama’s behavior resembles a highly indebted family’s taking an expensive round-the-world trip because it claims to have found ways to pay for it. It’s self-indulgent and reckless.

But the CBO estimate is misleading, because it must embody the law’s many unrealistic assumptions and gimmicks. Benefits are phased in “so that the first 10 years of [higher] revenue would be used to pay for only six years of spending” increases, a former CBO director, Douglas Holtz-Eakin, wrote in the New York Times on March 20. Holtz-Eakin also noted the $70 billion of premiums for a new program of long-term care that reduce present deficits but will be paid out in benefits later. Then there’s the “doc fix” — higher Medicare reimbursements under separate legislation that would cost about $200 billion over a decade.