There are plenty of land in the USA. However, that would mean destroying resources, plowing down the forests destroying animals' homes, draining the lakes dry and everything. A lot of dramatic changes would be made to the environment and that's not a good thing.
From what they say, if we didn't live on oil or coal, Earth wouldn't be able to sustain a population of more than 500 million human beings.
That's why the population exploded in a big way in the 18th century when they hit the first billion. Today, we are nearing 7 billion.
How is that a good thing? There's nothing good about that.
