Shares of federal spending in 2020 as projected by CBO’s baseline: Health care costs are the primary driver of the federal budget deficit. Congressional Budget Office projections for 2020 show that health care spending will consume more than 27 percent of federal budget.

This election ought to be about one issue, a referendum on health care reform.

Republicans say it’s about repealing Obamacare. Every candidate has pledged to repeal the law (as if presidents had such power) as a first act in office. But then what? What actions would follow to improve health care and dramatically lower the costs? Is there a conservative alternative? (I don’t see kicking young people off of Medicare as a solution -- that idea doesn’t drive health care delivery costs down).

But the “what next?” question remains a tough one for President Obama and the Democrats. The Affordable Care Act was a baby-step, a beginning, not an end.

This single election question matters because the cost of health care is the federal deficit. We are paying far too much for an inefficient health care system when we also have an aging population that is facing expensive medical care. Just think, if we solve this one problem, then the rest of the budget is manageable.

But if we fail to reach a national consensus then the budget obligations to pay for existing problems are many times greater than our resources.

The Congressional Budget Office puts it this way: “Projected growth in entitlement spending explains almost all of the projected growth in noninterest spending -- and the two big government health care programs that largely drive that increase. Medicare and Medicaid are responsible for 80 percent of the growth in spending over the next 25 years and 90 percent of the growth by 2080.”

And what drives that unsustainable growth? The CBO says two things: “The aging of the population and the rapid growth of per capita health care costs.” Remember the number of those eligible for retirement -- the baby boom generation born between 1946 and 1964 -- continues to swell. The number of older Americans is going up from 13 percent to 20 percent by 2035 while the share of Americans aged 20 to 64 is falling from 60 percent to 55 percent.

The military is a good example of the demographic riddle. Defense Secretary Robert Gates, in his last budget message to Congress, said “sharply rising health care costs are consuming an ever larger share of this department’s budget -- growing from $19 billion in 2001 to $52.5 billion in this request.” Gates argued for increased fees from working-age retirees saying the current system is unsustainable. “And,” he said, “if allowed to continue, the defense department runs the risk of the fate of other corporate and government bureaucracies that were ultimately crippled by personnel costs, in particular, their retiree benefit packages.”

Multiply the Pentagon’s dilemma across government. Or throughout the private sector. Then the scope of the problem is visible. Add to that landscape complexity those Americans who cannot afford health insurance. Medical issues don’t vanish because someone doesn’t have insurance -- they just get most costly and show up on another budget line.

That’s why I think a key part of reform is improving health care delivered via government agencies such as the Indian Health Service or the Veterans Administration. We also need to see how the health exchanges will work -- and to get hard data about their effectiveness. The Kaiser Family Foundation reports that there is wide, bipartisan support for the idea of exchanges. The trick, then, is to build on that consensus and make the exchanges effective.

So how do we Americans debate health care reform? We make certain this is the single issue for the 2012 election year.

Mark Trahant is a writer, speaker and Twitter poet. He is a member of the Shoshone-Bannock Tribes and lives in Fort Hall, Idaho. Trahant’s new book, “The Last Great Battle of the Indian Wars,” is the story of Sen. Henry Jackson and Forrest Gerard.

More from Mark Trahant:
Mark Trahant: Turning out the vote in Indian Country in 2012 (1/2)
Mark Trahant: Federal budget bill a transition to bigger cuts (12/19)
Mark Trahant: Payroll tax debate matters in Indian Country (12/12)
Mark Trahant: How can president have Indian Country's back? (12/5)
Mark Trahant: Fewer success stories arising in Indian Country (11/28)
Mark Trahant: Supercommittee again shows failure to govern (11/22)
Mark Trahant: Congress faces deadlines on big budget cuts (11/14)
Mark Trahant: Because even imperfect elections still matter (11/7)
Mark Trahant: Tribes deal with another brutal federal policy (11/1)