This is an interesting piece by Milton Friedman on the United States' healthcare system:
http://www.hoover.org/publications/hoover-digest/article/7298
Summary:
The current healthcare situation in the United States is largely a result of wage controls imposed by the government during WW2. In order to attract labor, employers began to offer healthcare benefits to circumvent the maximum wage laws. By the time the government caught on to this, it had become quite popular, and the government decided to make health benefits tax exempt because of political pressure.
Making health benefits tax exempt gives an incentive employees to take more of their earnings as health benefits. This led to the system of health insurance paying for
everything, instead of operating like every other type of insurance; as a backup in case something really bad happens. Auto insurance doesn't pay for oil changes, so why is health insurance paying for yearly physicals?
When people aren't spending their own money, they aren't as thrifty with it, so this leads to a massive increase in spending. By Friedman's estimate, half of the cost increase in health insurance in the last half of century is directly attributable to this.
The private sector did just fine before the government screwed things up. Look at the increase in average life expectancies against the increase in healthcare costs as percentage of GDP in the first half of the 20th century, which was largely a free market, versus the second half.