QUESTION:  
Do you think if we built cities on mars sometime in the
future, it would be like America soon with people flooding over there
as fast as they can? 

ANSWER from Donna Shirley on January 31, 1997:
No, it will not be cheap enough to travel to Mars for at least a hundred
years to let people "flood it".  What we have to worry about is not
overpopulating and destroying the earth while we are working on making Mars
habitable.