Climate change that caused a severe drought.It is also theorized that the Hittite's cities were destroyed by earthquakes.
Aegean civilization is a general term for the Bronze Age civilizations of Greece around the Aegean Sea. There are three distinct but communicating and interacting geographic regions covered by this term: Crete, the Cyclades and the Greek mainland.
Boomtowns is a community that undergoes sudden and rapid population and economic growth
they become ghosttowns because they typically characterized as "overnight expansion" in both population and money
For the answer to the question above,
Decrease in unionization. The Sunbelt was and is an area where unions are much weaker than in the old industrial areas. As people and jobs moved to the Sunbelt, unions grew weaker. I hope this helps