How does a society collapse?

So according to my reading of Diamond, a society collapses because its decisions about how to handle 5 major types of crisis result in extreme depletions of population and resources.

Saskatchewan is facing decisions about climate change, loss of trade and economic erosion such as loss of water, soil, minerals and forest. How do you think our decision makers will respond to this crisis?

Reflections on "Collapse"

I've been reading Collapse: How Societies Choose to Fail or Succeed by Jared Diamond. In a nutshell, this is my take on what he is saying.

Saskatchewan has recently experienced a resource increase because of the worlds need for oil making extraction from tar sands more viable. As a result, we have been experiencing a large population increase that has driven the cost of land and housing to unexpected heights. Increasing employment opportunities have supposedly offset the increase in prices, so we have suddenly become a "have" province ready to ride out the economic downturn. So we are at our pinnacle point.

We have recently felt the inkling of crisis as trade has decreased because of less need for resources such as timber, grain, fertilizer and a fall in the price of oil.
So what does Diamond say about how a societies response to crisis leads to success or failure? What should Saskatchewan do?