On Wednesday, Sen. Bernie Sanders introduced a single-payer health care bill that would create a national health insurance program, charting a stem-to-stern reshaping of the country’s health care system. The bill would make it so that Americans would get health coverage simply by showing a new government-issued card and would no longer owe out-of-pocket expenses like deductibles. But Sanders’ description of his measure omitted specifics about how much it would cost and final decisions about how he would pay for it.

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