This story:  "We must plan to house a growing population far into the future...."   
So no matter how many new houses they build, there will still be a shortage of housing.  No matter how much new transit they build, there will still be unbearable traffic congestion.  No matter how many new ways they find to tax fossil fuels, there will still be growing carbon emissions due to the growing population.  

But some time in the future the growth story must end.  How does that happen?  Does the population growth gradually slow to a graceful stop or is there something more dramatic that happens at the end point?