As employees we make our own career and in reality can not expect the same kind of support employees did in our fathers' time. Employers have made a radical shift over the last two decades, and I'm not sure that it is for the better.
I do strongly feel that there is an engine driving this. It's a philosophical, political, and economic force, and as such driven by opinion, luck, and whimsey as much as business sense.
The force is determined by who gets the organization's revenue. This revenue is a dynamic amount fixed by the good old fashioned balance sheet. In the past (and with fewer and fewer examples these days, the US Military is one), revenues were distributed to employees, with the company head rarely directly getting more than 7 times the average employee. This resulted in stable companies in times of great societal change.
As FDR is credited with creating the middle class, Ronald Reagan is credited with creating an investor class. As corporate CEOs and CFOs found themselves in the position of both employee and investor, the tide quickly shifted away from stable companies with stable mutually loyal workforces (driving a stable economy) to dynamic companies with employees considered necessary parasites and the first expense to be cut. The result has been an undeniable widening of the gap between rich and poor, a huge societal experiment pretty much forcing married couples to form two-income families, and a perpetually un-stable employed-class.
Is this good or bad? Well, it just *is*, and again as you say, employees must deal with it, and this isn't something we are taught in school.