We Americans typically think of insurance as a contract you buy to cover high-risk, low-probability events, such as car accidents, house fires, and premature death. Some aspects of health care fall into this traditional category, such as expensive emergency care for appendicitis or heart attacks. But most of us face these emergencies infrequently. Instead, the bulk of our medical care is for more routine or chronic ailments — relatively predictable, even if varying greatly in cost — such as high blood pressure, diabetes, and the flu. Yet we have come to expect our health “insurance” to cover most of the costs for all of these ailments, even though our home insurance doesn’t cover the broken furnace, rotting porch flooring, or decrepit wallpaper. Perhaps we should talk about “health care service contracts,” and perhaps if we did, we could have a more honest debate about what we expect from our health care system. Can market forces help keep costs down for all types of care or just for some? (Does anyone shop around for the most affordable ambulance or hospital while calling 911?) Can we bring back more limited health insurance policies for those who want them that cover only catastrophic events, or would that option destroy the economics of the broader system we’ve now come to expect?