Given that Medicare, not Social Security, represents the biggest threat to the budget, it's odd that the debt commission did so little to touch Medicare and the rising cost of health care, as a TPM reader notes:

I took a very quick look at this document and what's amazing to me is that they came up with these draconian cuts in Social Security, which is off-budget and currently in the black, but have barely anything for Medicare, where the government is hemorrhaging money.
They have several pages of material with almost no concrete ideas that adds up to minor savings (they claim savings that rise to $47 billion in 2020, but $13 billion of that comes from vague promises like "reform the sustainable growth rate" and "enact tort reform.")
If you look at the spending side of the federal budget, Medicare is the single item that drives growth out of proportion with the nation's population and income growth. Yet these guys seem to be hacking away at every other part of the federal budget more to make room for Medicare rather than contain it.

The answer is that the Affordable Care Act was a major step toward bringing the cost of health care into line. It wasn't the maximal possible step, but it probably was about as aggressive a step as could be taken at the moment. The commission just couldn't come up with a whole lot more.

Which is to say, the debt commission's report is premised on the (correct) analysis that the Affordable Care Act is a major advance for fiscal responsibility. Conservatives prefer to live in an alternative world where the ACA was a huge, budget-busting entitlement, whose repeal would somehow save the government money. But that is not the real world, and the debt commission's report reflects that.

Update: Former Bush budget staffer and anti-ACA crusader James Capretta makes the same point at National Review. He's livid that he commission builds on the cost-saving mechanisms in the Affordable Care Act. The question for conservatives, as Andrew Sullivan puts it, is, "Are you anti-debt or anti-Obama?"