The writer P.J. O’Rourke did a chapter on overpopulation in his book “All the Trouble in the World,” and if you had a population density comparable to, say, Manhattan, you could actually fit the entire population of the planet into a fairly small area (even smaller if you did Hong Kong level population density). Even at the population density of some suburban areas you could put everyone into an area smaller than the United States.
The writer P.J. O’Rourke did a chapter on overpopulation in his book “All the Trouble in the World,” and if you had a population density comparable to, say, Manhattan, you could actually fit the entire population of the planet into a fairly small area (even smaller if you did Hong Kong level population density). Even at the population density of some suburban areas you could put everyone into an area smaller than the United States.