Health insurance isn’t like other forms of insurance. It’s not protection against the unlikely; it’s insulation against the inevitable. Most people never use their fire insurance. Almost everyone uses their health insurance. Eventually.
The key is that not everyone uses their health insurance at the same time, or with the same frequency. Sick people use it more than healthy people. The elderly use it more than the young. Women use it more than men.
The trick to making any health-insurance system work is to attract enough healthy and young people into the insurance pool. Their low costs offset the care provided to elderly and unhealthy people, who drive costs up. This is the task that obsesses the Obama administration. It’s also the task that has begun to obsess its opponents.