Sure, patient expectations help drive the demand for more costly and more intensive care. But this factor pales beside the impact of business-maximizing suppliers who have strong economic incentives to offer such care. In health care, supply tends to create its own demand. The main reason U.S. costs are relatively so high is because U.S. doctors and hospitals treat each patient so intensively, using more higher-priced services and more tests than anywhere else in the world (resulting, of course, in higher incomes than elsewhere for physicians, hospital administrators, and insurers). Part of this, but not all, can be explained away by the effect of greater wealth on health—as a country gets richer, it can afford to spend more on less valuable health interventions. Medical competition—which takes places in the U.S. to an unparalleled degree—tends to raise overall costs, as the volume of procedures expands even as unit costs for services stay flat or even fall. The way doctors and hospitals are reimbursed—generally, still, on a case by case and item by item basis—encourages this trend.

Past efforts to change this pattern—such as managed care and per case payments to hospitals in Medicare—have substantially been outflanked by providers. Other countries have powerful forces pushing back on the demand side, usually a single government payer. The U.S. does not. Moreover, local hospitals and physicians tend to have so much market clout that they can resist efforts by employers and insurers to rein in spending, or to justify this spending on clinical grounds.

As John Wennberg and his Dartmouth colleagues have pointed out, with ever-increasing precision, regions of the U.S. that spend more on health per capita, adjusting for the sickness of their underlying populations, don’t get better outcomes. Higher spending regions may even do worse. Higher per capita spending, however, tends to be correlated with higher concentrations of specialists and hospitals. Where there are more specialists and hospital beds (in, say, South Florida), per capita annual Medicare payments soar. In Minnesota, where annual Medicare payments are roughly half those in Miami, there are fewer specialists and less medical competition. As Maggie Mahar argues in her excellent recent study of health care spending, Money-Driven Medicine, it’s reasonable to assume that different “tastes” for health services can account for a bit of this discrepancy, but not twofold differences in lifetime per capita spending.

To explain this, one has to turn to a different sort of culture—that of doctors and hospitals and insurers and the local standards of medical practice they support. One needn’t presuppose that doctors, in the main, are making crude calculations about how to push unneeded services on unwitting and fearful patients. Instead, referring patients to multiple specialists and routinely admitting patients with chronic illnesses to the hospital is simply a fact of life in higher spending areas (and on a aggregate basis, of course, in the U.S. as a whole), and a potential red flag in others. As you’d expect, patients learn to adapt to the prevailing medical culture. In Minnesota (or Canada), they tout the excellence of their primary care doctors. In Miami or New York, they tend to be more anxious if a specialist (or two or more) hasn’t reviewed their case.

Writing about rising health costs without giving pride of place to the power of medical providers, and the cultures they create, is like playing Hamlet without the Prince of Denmark. To be sure, patients should be part of the solution to needlessly rising costs. If they live healthier lives, question the value of procedures, and scrutinize their bills, that would be helpful. In fact, there’s a growing body of evidence that when patients and their families are fully briefed about their condition and about treatment alternatives, they tend to be more conservative than physicians. They may even be willing to forego care that prolongs life slightly at immense costs. But putting the onus on patients to control costs is misguided thinking that gives unwelcome support to short-sighted solutions, such as health savings accounts.

Leif Wellington Haase is a Senior Program Officer and Health Care Fellow at The Century Foundation.