system
A chat on subreddit /r/PoliticalCompassMemes
human
Our economy is so massive because the US has had every advantage possible since our creation.

The biggest reasons are room to grow (large population over a large landmass) and our industrial base has never been destroyed (no largescale setbacks due to war).

Taking the smartest and hardest working from other places is largely a new development for the US
gpt
Our river system and size of arable land is also insane.