When settlers first came to the colonies of North America in the 16th and 17th centuries they were amazed by the tremendous natural resources and the rich soil that seemed to make everything grow. Unfortunately they took it for granted that these bounties would last forever.

Southern farmers in particular adopted a very bad policy of using up the land until it was barren and then simply moving on to new property where they started the process again. The problem was that eventually they were going to run out of land and the system would collapse.

We seem to have made a similar mistake in 20th century economics. For decades we’ve fueled economic growth, both personal and business, on debt and confidence in future growth. While this is helpful in the short term you can’t count on it lasting forever. Just as the rich farmland did not last forever neither did the economic riches.

The housing industry in particular was hurt by this process as buyers dumped trillions into real estate depending on the fact that the value of the property would grow. When it did not the housing bubble burst and we got the collapse in the mortgage industry.

The same thing has happened in most other industries (stock markets come to mind) but in this case there was so much money involved that it helped send us to the current mess. While certainly there are other causes of the crisis (ranging from corporate greed to inadequate regulation and beyond) the basic problem stems from the consumer presuming that the ride will never end.

In a report issued this week the World Bank is predicting that things will get worse before they get better. They seem to expect that while 2009 will see continued slumps that 2010 will be a time of recovery. Obviously we all hope that the recovery does come in 2010 but I am not sure that it will.

My concern is that we have a couple more shoes to drop in the economic downturn. The first is the increasingly likely collapse in the commercial real estate market, which is brought on by the failure of a number of major renters in shopping malls and a slowdown in construction.

I also think we could see a blowup in the credit card industry as more and more people declare bankruptcy, and this could hurt banks in their efforts to climb out of the mortgage mess.

It is unfortunate that we are seeing so many of these problems at once but as many economic experts have pointed out these problems have been developing for several decades and each was just waiting for one more little push to shove them over the edge.