That may be, there are always cities growing and other cities shrinking.
What I am referring to, are much bigger however.
America itself is shrinking now.
We need to bring back jobs to America.
The loss of a common identity; of social cohesion; magnifies all other problems; makes it infinitely more difficult to even ameliorate other problems.
Detroit went down further than more Conservative cities, precisely because of its being the victim of egalitarian/collectivist values (i.e., the philosophic underpinning of Communist values).
This was all predictable--completely predictable. To understand the general effect of the earlier agitation, to which I refer, see The Greatest Mischief Ever Wrought.
Or, to approach the questions from a positive direction; that is, to understand why America prospered so greatly before the Leftist policies (social engineering, etc.) brought about the present problems, consider America-- Grounded On Experience & Reason.
William Flax