What you are about to read is anything but the current conventional wisdom: President Barack Obama has an opportunity to have such a positive impact on the federal budget that he could end up being considered one of the most fiscally responsible presidents of all time.

[IMGCAP(1)]How could this happen? It begins with what is now incontrovertible: Obama has “permission” to preside over an increase in the federal deficit to levels never previously imagined.

Even though a few might prefer it not happen at all, or that it get to this level differently, a trillion-dollar deficit, which heretofore was so completely unthinkable that it was never mentioned in polite company, has now become a fait accompli, inescapable and, most important, politically acceptable.

As a result, Obama has the ability to support policies that will dramatically raise the deficit. And even though that previously unmentionable trillion-dollar deficit will become so commonplace during the first two years of his administration that it will no longer result in raised eyebrows, the Obama White House will be able to credibly claim that it is fiscally responsible. (For the record, and even though no one has said so officially, my back-of-an-envelope estimate shows that the fiscal 2009 deficit is more likely to be closer to $2 trillion than $1 trillion. Even that number won’t affect the administration’s budget credentials.)

The reason for this is simple: The demand that the president deal with the economy is so strong and his proposed higher deficit is considered to be the right medicine by so many that it will be very hard to successfully characterize this White House as being fiscally reckless almost regardless of what it proposes, supports and approves during its first year or two. Few other presidents in history had a similar opportunity.

The second reason Obama could end up being considered one of the most fiscally responsible presidents of all time is that the previously unimaginably high deficit means that as soon as the economy allows it, there will be a strong, and probably bipartisan, consensus that deficit reduction has to happen.

This is obviously the mirror image of the initial reason for Obama’s budget opportunity. First, he’ll be able to increase the deficit without harming his fiscal responsibility credentials because the political opposition to how much it rises as a result of his policies will be relatively muted. But as soon as the economy unambiguously is understood to be recovering, the need for the president to deal with the budget will replace the necessity of his dealing with the economy. This will mean that the previously politically unacceptable deficit-increasing proposals from the first year or two of the Obama administration could be replaced with similar previously unacceptable deficit-reduction spending cuts and revenue increases.

Despite the fact that a balanced budget has almost always taken on religious qualities throughout American history, there have been few times when a bipartisan consensus existed that the deficit should be reduced. Even during George W. Bush’s administration, when the deficit repeatedly hit record nominal highs, there was widespread disagreement about whether action was required.

That’s not likely to be the case this time. The annual trillion-dollar deficits and multitrillion-dollar increases in the national debt in 2009 and 2010 will change the discussion from whether the deficit needs to be addressed to how it should happen. The bond market, which was so instrumental in forcing the Clinton administration to deal with the budget, will again likely be an active and influential participant in the debate as the concern shifts to continued government borrowing that could raise interest rates and stop the recovery in its tracks. That will provide elected officials with the permission they need to move from their previous feet-in-cement positions opposing certain spending cuts and tax increases. Reducing the deficit at that point will become as much a fait accompli as increasing it was before.

The fact that a consensus to reduce the deficit will exist is the third reason Obama could end up being considered one of the most fiscally responsible presidents in history. Why? This consensus, the first that will have existed for well over a decade, will allow the president to propose, Congress to support and both branches to implement a new budget process.

Having a consensus about what needs to be done on the budget has long been the key requirement for putting a budget process in place. The Congressional Budget Act was only enacted in 1974 after a clear consensus developed that Congress needed a process to deal with the executive branch on budget issues. That was replaced in 1985 when a consensus developed that deficit reduction rather than just the outcome-neutral 1974 process was needed. Gramm-Rudman-Hollings was the result.

There’s been a great deal of discussion since the mid-1990s about a new budget process, especially since most of the major enforcement provisions of GRH were allowed to expire. Nothing has been adopted, however, because there has been no agreement on what a new process was supposed to accomplish. That will change completely, however, if what happens on the budget during Obama’s first two years creates a consensus that reducing the deficit again has to be the priority.

There are already indications all of this is starting to happen. The trillion-dollar-plus deficits projected for 2009 and 2010 are being agreed to, but there is increasing talk from the White House about what will need to be done afterward to get control. There also seems to be growing interest in tackling entitlement spending and tax reform — two previously verboten subjects — when the time is right. And the president is already talking about fiscal responsibility summits and entitlement reform initiatives that sound remarkably like process changes in the making.

All of this means that, as far as the budget is concerned, the first two years of the Obama administration could be among the most active, and confounding, of any presidency in recent memory.

Stan Collender is managing director at Qorvis Communications and author of “The Guide to the Federal Budget.” His blog is Capital Gains and Games.