During the campaign, then-Gov. Bush was criticized as a clumsy public speaker with a tax-cut plan built upon fuzzy math. In his first major speech since his inauguration, President Bush revealed himself to Congress and the nation Tuesday as a fine and sincere public speaker. The math still needs some clearing up.

The agenda the president laid out is ambitious – major new initiates in education, health care, the environment and defense, coupled with a significant paying down of the national debt, Social Security reform and, of course, that massive $1.6 trillion tax cut. The tone of the well-crafted speech – refuting the tiresome anti-government rhetoric too common among Republicans, the strong support for education, the vow to end racial profiling by police – conveyed a true desire to reach beyond party lines. The structure of the speech – dealing with the new initiatives and standing obligations first – clearly was intended to convey the message that the $1.6 trillion truly is leftover money that ought to be returned to the taxpayers.

That is where the fuzz comes back into the picture, it is the inevitable consequence of launching new programs while slashing revenues. For the first year, Mr. Bush’s budget adds up by leaving things out. An increase in military spending stays where the Clinton administration had it until reviews of defense programs and the missile-defense proposal are complete. The cost of the president’s plan for private Social Security accounts, estimated at hundreds of billions, is deferred for a year or two by a study commission. The $150 billion over 10 years he proposes for a Medicare drug benefit is only the start of an ongoing entitlement with unknown costs.

Those are just a few of the “known” uncertainties. The proposal presumes a lot about the economy, of the nation and the world, over the next 10 years. There is, after all, a cautionary element to Mr. Bush’s Goldilocks-like assertion that $1.6 trillion is “just right” – she, too, could only cross fingers and hope the bears wouldn’t come home hungry for something other than porridge.

To make the math work, the Bush administration already has had to resort to some number massage. The claim that only $2 trillion of the $3.2 trillion in publicly held debt is “available” for paying down due to technical reasons is being assaulted by financial experts across the political spectrum. The $1 trillion “contingency fund” is the result of that possible mirage. The surplus estimates themselves are based upon unrealistic restraint during an entire decade. An economic downturn of any significance is simply out of the question. There is no question that Americans are entitled to tax relief, but weight the risk of enormous deficits against the modest benefit this tax cut offers middle-income Americans and the public’s lukewarm reaction is understandable.

It was impossible to watch Mr. Bush the other night and not think of, to some extent at least, of Ronald Reagan, another Republican who took office to diminished expectations, who reached across party lines, who exuded unbridled optimism. The genuineness is a welcome change from the recent cynicism, but Mr. Bush and his budget advisors would be wise to remind themselves that this country has just dug itself out of the enormous deficit it ran up the last time huge tax cuts and increased spending collided with an economic downturn. In the end, it’s not about speaking ability, sincerity or optimism. It’s just about the math.