President Obama wants to “turn the tenor of the political debate this week,” said Mark Silva in the Chicago Tribune, from “massive new spending to ‘fiscal responsibility.’” Toward that end, he hosted a “fiscal responsibility summit” at the White House, is addressing a joint session of Congress Tuesday night, and will unveil a budget that promises to cut the federal deficit in half by 2013. Even if he hits that target, the deficit will be $533 billion.

Obama’s budget plan has both “potential benefits and drawbacks,” said Stephen Spruiell in National Review Online. On the plus side, he’s promised “more honest accounting” by bringing the Iraq and Afghanistan wars into the “regular budget.” But he will probably also resort to the “government’s biggest accounting trick”—underestimating the future costs of Social Security, Medicare, and Medicaid.

It’s “much easier to host a ‘summit’ on fiscal responsibility” than to act fiscally responsible, said Rich Lowry in the New York Post. “Conveniently,” Obama’s budget discipline will come from “doing all the things he already wanted to do”—scaling back the Iraq war, “raising taxes on the rich,” and reforming health care. The first two will at least cut the deficit, but health care will be a stealth “budget-buster.”

Obama may not be able to halve the deficit, said Peter Beinart in The Daily Beast, but he is “wise to make the pledge anyway.” Republicans are talking tough about “budget-busting” now, after years of spending profligately and cutting taxes, and “Obama is calling their bluff.” But he’s also giving Democrats notice that he’s serious about reigning in entitlement costs, especially Medicare.