Steve Chapman:

If Medicare were a bank, federal regulators would be closing its doors, selling its operations and sacking its managers. Thanks to soaring costs, the program is fast running out of money -- even though it pays such low fees that many doctors refuse to take Medicare patients. Meanwhile, Medicare fraud costs taxpayers some $60 billion a year, according to a report by CBS's "60 Minutes," making it among the most profitable fields for felons.
That's our experience with government-run health insurance for the elderly. So what do congressional Democrats propose to do? Offer government-run health insurance to everyone else.

Betsy's Page has some good comments on the public option.