Will mandating the purchase of health insurance lead to universal coverage?

The biggest domestic-policy difference between Hillary Clinton and Barack Obama almost certainly concerns health care. Mrs Clinton proposes individual mandates, which would require people to buy health insurance. To help the poor afford it , she promises subsidies from the government.
Boosters of the individual-mandate approach, with which Massachusetts is now experimenting, hope that it would lower average costs by forcing the many young and healthy people now currently without coverage to buy a health plan. As Mrs Clinton pointed out this week, such people do get health care, but in the most expensive way—by turning up at emergency rooms uninsured.
Maybe not, if a report issued by the official Centres for Medicare and Medicaid on February 25th is to be believed. The government's actuaries calculate that even without any new universal-care scheme, spending on health care in America will reach nearly 20% of GDP by 2017, up from about 16% last year, with Medicare spending nearly doubling over that period.