President Obama can save entitlements through reform – but will he?

The White House is pouring millions of taxpayer dollars into its public relations campaign to build public support for — and understanding of — Obamacare. Imagine what a fraction of that effort might do if directed at educating voters about the dangers of exploding entitlement costs. Here’s what a newly enlightened public might learn:

–We haven’t “fixed” the federal debt. It’s true that sequester-mandated cuts — combined with Fannie Mae and Freddie Mac’s $131 billion payback to the Treasury and a slightly better economy — have improved the short-term outlook. But while the debt as a share of the economy will drop over the next four years, it will start to rise again after 2018, reaching 85% of GDP by 2030 — and then swamping the size of the economy at 136% by 2050 and 248% by 2080, according to estimates by the nonpartisan Committee for a Responsible Federal Budget (CRFB).

–Despite a much-touted slowdown in the growth of health care costs (largely because of a lagging recovery, according to studies), Medicare spending will rise from $500 billion this year to more than $900 billion by 2023, according to another nonpartisan debt group, Moment of Truth. As baby boomers retire, raising taxes or slicing benefits will become a brutal necessity. The Medicare Hospital Insurance Trust Fund will still go broke in 2026 — and 10 years later the Social Security trust fund will be exhausted.

–The debt, driven by entitlement costs, still hangs like a toxic fog over the U.S. economy. The prospect of higher taxes contributes to business uncertainty. The elephant of entitlement spending squeezes out resources for infrastructure investments that would boost American competitiveness. “We are borrowing to consume rather than invest,” notes CRFB president Maya MacGuineas. That means a drag on economic growth, with fewer jobs, slower wage growth, and limited opportunities for our children and grandchildren.

MacGuineas is part of a cottage industry of ex-lawmakers, budget officials, and policy wonks who really do qualify as public servants for their willingness to keep beating the drums on the dangers of the debt long after the media’s short attention span has moved on. Their CEO-backed Fix the Debt campaign — led by Alan Simpson and Erskine Bowles, who chaired the namesake presidential commission that the President ignored — is well funded and has national reach. But the campaign has come under attack from those on the left who deride its “ruthless” austerity agenda, as the latest chapter in a rich corporate interests vs. everyone else class war.

That’s where President Obama could step in to make the case that reforming entitlements means rescuing them. With both sides of the aisle coming to an agreement on cost-control measures such as means-testing and Medicare cost-sharing, all roads lead to the need for leadership from a President whose liberal-activist base is well practiced in the art of demonizing anyone who dares question the growth of entitlement programs.

Debt-control advocates are hoping that President Obama will see entitlement reform as a way to leave an important legacy in his second term. That’s unlikely. The President opened his second term with an inaugural address making clear that “hard choices” on spending would take a back seat to the “commitments we make to each other: through Medicare, and Medicaid, and Social Security.”

Improved short-term numbers on the debt and deficit have given the White House convenient breathing room to table those hard fiscal choices. The media won’t notice the issue again until this fall, when a crisis-driven Congress launches yet another noisy skirmish over whether to raise the debt ceiling.

This White House is satisfied with leaving a legacy of ending two wars and imposing a complex and divisive Obamacare on one-seventh of the economy. But if he ever did take up the fiscal sword to protect future generations, Obama might start by borrowing MacGuineas’s point: “It’s going to hurt people more if we wait.”

This story is from the August 12, 2013 issue of Fortune.