Population projections in the U.S. suggest that the population of the Country will increase by 150 million between the years 2007 and 2050. Many think that this is absurdly high. Unfortunately, it may be unrealistically low. The population of the U.S. grew by 150 mil from 1950, when the population was 150 mil, to 300 mil in 2007 - a period of 57 years. If the population increases to 450 mil by 2050, it will be a straight line growth. Looking at the growth in the U.S. over a longer time period, however, suggests that the rate is more likely to continue to be exponential. The question, of course, is where will these people live. For a long time, the parts of the Country that were seeing the most growth are those areas like Arizona and Texas. Jonathan Barnett and Peter Calthorpe have shown images of Florida and California with projected growth looking like mold growing across those States. While part of the answer there is promoting compact growth to avoid the loss of open space, another answer should be the repopulation of the cities in the rust belt, including the line of cities across New York State from Troy to Buffalo. The Hudson River Valley is the key connection between New York City and that string of cities. The Mid-Hudson Region should be understood as part of a National solution to the future.