Why doesn't Obama just let everyone without health insurance sign up for medicare?

If I need to fix the porch screen I do not tear down the whole house, the thinking on this health thing is ludicrous to me.
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that is the same question a lot of people ask including myself. It leads me to wonder if this is an effort to insure the poor, or a government takeover. The current government plan isn't about making insurance more affordable. The plan will be administered by the government just like medicare. It will be sold at 10% less than current option(according to Obamas estimates) subsidized by tax dollars. It will require strict regulation of private companies that the government will not be held to. It is designed to put private companies out of business.
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