Going underwater? Learn to swim

With the housing boom and bust of the last years a fairly new phenomenon has been born, I am talking about 'underwater mortgages'. People were blind and naive to think that the housing market will incessantly go up. Banks, mortgage intermediaries, real estate salesmen, governments and even some economists (that is the most unbelievable part) helped uninformed people think this was true and was going to be for ever after. Of course they all had their own interests in making this fallacy last as long as possible, making the mother of all bubbles grow forever. "Buy a house! It pays by itself" Can you already see the problem with this?