President Obama has gone out of his way to defer to Congress on some his biggest legislative priorities in the areas of health care, energy, education and immigration. And his detached position on the political upheaval in Iran prompted skeptics on Capitol Hill to wonder if the president was leading or allowing events to dictate a response.

Time, then, for the commander-in-chief to bring out the stick hidden under his desk and silence those questioning his resolve.

On Wednesday, Obama issued the first veto threat of his presidency, stating he would refuse to sign the House's version of the fiscal 2010 defense authorization bill (HR 2647) if it includes either of two provisions: $369 million in advanced fiscal 2011 procurement funds for the F-22 aircraft or $603 million for development and procurement of the alternative engine program for the F-35 Joint Strike Fighter.

The White House is trying out a new argument to ease concerns over those sky-high estimates of the cost of overhauling the health care system. The federal government wouldn’t really be spending more money on health care, the argument goes — just shifting money that’s already in the system and spending it more efficiently.

It’s a dangerous argument for the White House to make, though, because it’s too easily shot down.

On ABC’s Good Morning America this morning, Melody Barnes, director of the White House Domestic Policy Council, used the argument to dismiss the Congressional Budget Office’s estimates that various versions of the health care bill could cost anywhere from $1 trillion to $1.6 trillion.

“I think people thinking that this is brand-new money that’s being printed,” she said. “There’s already $2 trillion worth of health care that’s being spent already. This is redirecting that money so that it’s more efficiently and effectively used and so that people are getting better quality health care.”

President Obama continues to enjoy strong public approval ratings in virtually every category, except when it comes to spending and the deficit.

And though White House strategists swear they don't fixate on day-to-day blips in public opinion, they surely are concerned that the administration's budget proposals are projected to swell the deficit above $1.8 trillion this fiscal year -- a record in dollar terms and also the biggest deficit as a percentage of the gross domestic product since the end of World War II.

So it was hardly coincidence that Obama on Tuesday took a high-profile vow of fiscal responsibility by calling for a return to statutory "pay-as-you-go" treatment for legislation. The deficit-control rules were first written into law in the Budget Enforcement Act of 1990 (PL 101-508), but Republicans who controlled Congress for most of the current decade allowed them to lapse at the end of fiscal 2002, preferring to require offsets for new entitlement spending but not for tax cuts.

Poor Harry Reid. At this afternoon’s regular Tuesday press briefing, the Senate majority leader was trying to talk about the credit card regulation bill the Senate had just passed, a major priority for President Obama and congressional Democrats. Clearly, he wanted to get lots of questions about that.

But all the reporters wanted to talk about was the apparent Democratic rebellion against Obama on another front: the Senate leadership’s decision not to fund the $80 million Obama wanted to close the Guantánamo Bay detention facility. The money will be stripped out of the supplemental spending bill for the Iraq and Afghanistan wars.

The mass pledge by health care providers today to reduce $2 trillion of spending reflects some cold political calculations by hospitals, doctors and other key players about President Obama's to reshape the U.S. medical system.

Chief among these is that Obama is likely to prevail in his efforts to expand access to public insurance and allow the government to negotiate Medicare outpatient prescription drug prices.

In speeches and policy pronouncements, Obama has successfully twinned an overhaul of the health system with the broader economic recovery. And with fortified Democratic majorities in both houses, the administration is working hard with Senate Finance Chairman Max Baucus, D-Mont., and other allies to move legislation in the next two months.