From the Examiner:

As Congress and the White House began to discuss health care reform, author and journalist Virginia Postrel offered a modest suggestion: If simple and decisive government action can curb costs in health care, as Obamacare advocates claim, why not begin by fixing Medicare before rushing in with sweeping changes to the entire system? The government already runs half of America’s health care system. According to federal statistics, federal and state governments together spent virtually the same amounts on health care in 2007 as did all private insurers and patients combined — $1.036 trillion and $1.045 trillion, respectively. Medicare, which serves the elderly, is the largest public program, accounting for 19 percent of all health care spending in the U.S.

Emphasis mine.  More here.