This summary completely ignored other key aspects of the book: The impact of declining birth rates and demographics on societies The impact of food independence (or lack of it) on global society if trade breaks down. The impact of key materials for manufacturing if trade breaks down.
I agree with the impact of oil dependence but this summary oversimplifies the book. If global trade truly breaks down, the lack of oil will be the least of our problems. Very few countries are blessed with the energy, food, material and demographic resources to maintain modern society. The US is one of the very and by far the most blessed.
What Zeihan predicts is scary for the US…but should be terrifying for most of the rest of the world.