[dragonwriter]

> To counter this, these people's life experience is entirely of the 20th century. A world of linear growth

Er, no. An earlier spot on the same exponential curve, but there hasn't been a “world of linear growth” in the West since the Industrial Revolution. Maybe, more properly, the preceding Second Agricultural Revolution.

> and clearly defined national boundaries where information can be controlled.

Not really; the breakdown of that feature was recognized and commented on widely throughout the 20th Century, notably in the context of:

(1) the rise of international revolutionary communism,

(2) the rise and increasing dominance of multinational corporations,

(3) the rise of international Islamism