When Congress returns to work after pausing to reflect on the horror of the Arizona shootings, health care repeal will top the agenda for Speaker John Boehner and the Republican Party. “Obamacare” galvanized opposition to the Obama presidency within Republican and independent ranks. And few issues within health care generate such a visceral and often hysterical response as the “individual mandate”—the obligation that all people participate either by purchasing insurance or paying a tax whose proceeds would be used to defray the costs of uninsured health care and reduce premiums.

What is bizarre about the Republican opposition is that the individual mandate is an extraordinarily conservative concept—one at the core of former Republican Gov. Mitt Romney’s health prescription for Massachusetts, and one designed to address the age-old Republican critique that folks without “skin in the game” are freeloaders on society.

Put to one side for the moment the question of commerce clause jurisdiction—whether the federal government has the constitutional power to implement the idea. That issue will be resolved by the Supreme Court, but is not the cause of the visceral response to the individual mandate. Conservatives claim to be outraged that any government—federal or state—could require them to participate in the health-insurance marketplace.

Yet in a series of conversations I have had with senior Republicans—both on and off my CNN show—those individuals have conceded that the idea makes sense, and is conservative to boot.

Let’s start with a couple of facts nobody disputes. Federal law requires hospitals to give emergency care to all people—regardless of insurance coverage. The annual bill for care delivered by hospitals to uninsured individuals is more than $40 billion. Those costs are reimbursed to hospitals through multiple reimbursement programs—state and federal—all designed to cover what is called “charity care.” All the funds for these reimbursements come from you and me—in the form of either higher taxes or insurance premiums. Our dollars are funneled to the hospitals to cover the cost of covering the uninsured. Those who get the care yet have no insurance and pay no bills are freeloaders whose costs have been shifted to everybody else. These freeloaders are the very sorts of people Republicans usually love to deride—for they eat from the trough of public benefits yet contribute nothing.

These uninsured individuals have made an economically rational decision—but a selfish one. Why pay insurance premiums when they can rely on hospitals to provide emergency care anyway? Moreover, they may gamble that the value of the health care they consume will be less than the cost of the premiums they will pay. Shifting the cost of their care to others seems just fine to them. Those of us who pay premiums and taxes are covering the cost of these freeloaders. Not fair, we cry!

The remedy is conceptually easy: Everybody should buy some form of insurance or pay a tax whose proceeds are used to cover the appropriate health costs. That amount can be—and is, in the health care reform law—calibrated to one’s income.

Nobody with whom I have spoken has any alternative idea that makes sense. A few conservatives offer a canard: the fallacy that people can “opt out” of the health care marketplace. We all participate, from the moment of birth, and we all incur and generate costs. From required life-saving inoculations to the high costs of end-of-life care, we all consume. The only question is whether we all pay.

The pseudo-libertarian argument that we should all be free to opt out was rendered irrelevant when we required that hospitals give care to anybody in need. Fortunately, nobody is arguing against this humane concept. So the only remaining question is how we cover the costs.

The requirement that insurance carriers cover those with pre-existing conditions also makes full participation logically necessary. Without the mandate, rational people would wait to acquire coverage until they were very ill, driving the cost of coverage through the roof, thereby defeating the very purpose of insurance.

In a nearly identical context that causes absolutely no political controversy—auto insurance—our policies are similar in every single state. Nowhere can you drive without having auto insurance. Why? Because when you drive you create potential costs that must be covered. So every state has made the decision that if you want to drive, you must be covered.

Are there some people who opt not to drive? Of course. So they don’t need auto insurance. But you can’t opt out of health care. We all consume, all generate costs, and all want to pay as little as possible. But those with no insurance at all, who skip payments altogether, are merely shifting the costs to the rest of us. By having them pay their fair share, by making them have some “skin in the game,” we are accomplishing what Republicans have always said they want to do—make free-riding impossible.

So why are Republicans so against the idea?

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