The next president will inherit this harsh reality:

The cost of America's health care system is unsustainable and will cripple the federal budget in the next few years if current trends in spending continue. There are only two routes to take — raise taxes or curtail services. Neither option is palatable to most politicians, especially those seeking office in a presidential election year.

Thus far, the campaign between Democrats Hillary Rodham Clinton and Barack Obama has been largely confined to how to get the more than 47 million Americans without health insurance covered. They offer very similar proposals that would combine government-subsidized plans with employer-based coverage. The main difference between them is that Clinton would require all Americans to purchase coverage, while Obama would phase in his universal coverage plan by mandating insurance for children first.

To pay for the expansion — estimated to run at least $110 billion — both would repeal tax cuts for the wealthiest earners. Neither offers any hint that taxes for most Americans might increase, or that benefits under a government-backed plan might have to be restricted.

Sen. John McCain, the likely Republican nominee, wants to use tax policy to make insurance more affordable. Universal coverage has never been a plank in the Republican platform, nor is it expected to be this year..

Unfortunately, what we don't hear on the campaign trail are details about what can be done to stem the steep rise in costs of the nation's two largest government-sponsored health plans — Medicare and Medicaid. The two programs cost $627 billion last year, or about 23 percent of all federal spending. Over the next 10 years, spending on both will double and account for more than 30 percent of the federal budget, according to the latest estimates from the Congressional Budget Office. With that amount devoted to health care, other federal initiatives — from transportation to education to defense spending — will be impossible to sustain without a substantial tax increase.

Both programs — Medicare for the elderly, Medicaid for the poor and disabled — are growing faster than the national economy or the tax revenues used to finance them. Medicare, in particular, is in danger. The trust fund used to pay the hospital services of Medicare patients will run out of money in 2019. Over the next decade, the number of Medicare beneficiaries is expected to go from 44 million to 55 million as the baby boom generation enters its government-financed health care years.

But the increased spending on the two programs is not being driven by the population bulge alone. Medicare costs per beneficiary are also rising faster than can be sustained with current funding formulas.

New medical technology — diagnostic tools used to screen for cancer, heart disease and other chronic conditions, as well as new devices and therapies to treat common disorders — are contributing to higher costs. Any suggestion that Medicare and Medicaid might save money by more selectively employing these new tools is sure to generate charges of rationing.

In recent years, federal officials have tried to slow the cost of the programs by restricting payments to physicians and tightening reimbursements to hospitals and other providers. State Medicaid programs, following in the footsteps of their federal colleagues, have done the same with Medicaid reimbursements for providers. That approach has put quite a squeeze on providers — not just public facilities like Atlanta's Grady Memorial Hospital but also private-practice physicians, especially those offering primary-care services.

And then there's this dirty little secret about the nation's health care system: When Medicare and Medicaid squeeze payments to providers, those same providers seek to increase fees to private insurers, which in turn leads to higher premiums for employers and workers on group health plans. Add to this the 47 million uninsured, and you can begin to see the vicious cycle of "cost shifting" that keeps the $2.1 trillion American system in turmoil.

Democrats are right to push universal health insurance as the first step toward a solution. A significant body of research in recent years, much of it funded by the Atlanta-based American Cancer Society, provides ample scientific evidence that those covered by insurance are diagnosed earlier with cancer and live longer than those who aren't insured. Besides the moral imperative — this country remains the largest in the industrialized world that doesn't guarantee coverage — there are economic costs associated with a lack of insurance, including bankruptcies and broken families.

The plans the Democrats offer are clearly preferable to the slower, marketplace reforms being promoted by McCain and still championed by President Bush. The GOP plan would offer refundable tax credits of $2,500 for individuals and $5,000 for families to purchase private-market plans. But even with the tax break, these plans may offer scant benefits. And most of the plans will come with a hefty yearly deductible, which would barely put a dent in the ranks of the 47 million now without insurance.

Still, whoever walks into the White House next January will face a formidable challenge in matching the worthy goal of increasing coverage with a genuine need to restrain costs. That will require a strong leader willing not just to reach out to those who disagree, but one who is willing to be honest with voters about the choices the country faces.

— Mike King, for the editorial board