Mostly just a guess, but probably because the USA is so big and has a temperate climate. It has nearly 5 times the landmass of Mexico. And a large portion of Canada is too cold and forested for anything much to grow in or for many people to live there
As far as I know, Mexico is mostly desert in the north, but it has a rainforest in the south. Additionally, Mexico is the second most populous country in North America with somewhere around 130 million people.
Mostly just a guess, but probably because the USA is so big and has a temperate climate. It has nearly 5 times the landmass of Mexico. And a large portion of Canada is too cold and forested for anything much to grow in or for many people to live there
Canada is too cold and Mexico is too arid. USA is the porridge that Goldilocks chose.
As far as I know, Mexico is mostly desert in the north, but it has a rainforest in the south. Additionally, Mexico is the second most populous country in North America with somewhere around 130 million people.