Why McCain's idea of buying mortgages is a bad idea

There appears to be a growing consensus that if McCain's plan for the government to buy mortgages was implemented, it would guarantee a loss for taxpayers and let lenders off the hook for their bad lending behavior.

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UPDATE

Here is what financial wizard Bill Gross had to say about injecting capital into the banking system, along with other issues relevant to our economic situation. From Morningstar:

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