In Hot, Flat, and Crowded, what does Thomas Friedman mean when he says the earth is hot, flat, and crowded?
What Friedman is saying in this book is that there are three major issues that face the United States. The US will need to learn how to adapt to all of them in order to succeed going forward.
The word "hot" refers to the fact of global warming. The word "flat" refers to the idea that the world is becoming more competitive economically and jobs that used to be done in the US can be moved overseas. Finally, the word "crowded" refers to population. Friedman is saying that the population is increasing and that people in general are getting richer. This means that they want to consume more things, which leads to faster depletion of the world's resources.