What is so bad about single payer health insurance?

I believe I've heard Clinton accuse Obama of wanting single payer health insurance in a previous debate. Basically something like Medicare where the money comes from one source--most likeley government? people are making a big deal about it. What is this exactly and is that a bad idea? i find it quite intriguing..
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Well, the term speaks for itself. SINGLE PAYER Health Insurance is a MONOPSONY. Like a Monopoly, i.e. one seller and its evils, Ms Clinton and others want only one Buyer of Health Care, i.e. a monopsony. Just like you do not want to only have the choice to buy a Yugo, you should be able to buy your medical care by yourself. Overtime Ms Clinton's medical care will use the power of government to dictate price and procedures of medical care --- You see this in miniature in cities and town where one employers is the 1000 kg gorilla in the market. If you are a MD or Hospital you accept what the employer sets for payment or you starve or move away. With the government you cannot move away. Your medical privacy will be trashed --- see what the current status of medical privacy under Kennedy and Clinton at the site below. What is bad about it is that it destroys incentives for everyone. It destroys the incentive of the young to stay healthy because they will never bear the cost of over-eating, drug use, STD because these costs would be passed on to the population (subsidize bad behavior). It is unfair to the elderly, who will be the biggest buyers of health care in the next 10 years to the point that Ms Clinton will (to safe funds that cannot exist), will refuse treatment to grandma and she will die sooner and more painfully then she would if she could buy her care. Think of only being able to buy your clothes from the Mao Boutique --- one colour, one size, one style. It is not the role of government to pay for health care --- it is a restriction on personal freedom. Do you know anyone on Medicare? Do they like it?
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