By providing an incentive for the purchase of ever-more-generous health insurance, the tax exclusion has been a major driver of health care inflation. By covering more services, offering more choices and lowering the costs people experience, expensive plans encourage people to use more health care services and, when there are options, more expensive services.

For instance, patients might use the emergency room for sore throats, or go to specialists instead of their primary care physician to adjust their blood pressure or thyroid medications, because their more generous insurance plan lowers the cost of using these expensive options.

This is no small matter. According to several economists’ recent analyses, the tax exclusion may account for a more than 30 percent increase in health care spending for those with employer-sponsored insurance, because of this incentive to use more health care services.