alt Hacker NewsTech development != tech tree, history is nonlinear and ecological. Linear, unlockable "tech trees" are an ahistorical fantasy necessary to make some video games fun and digestible. Applying them to the real world is like trying to win a war by replicating the Battle of Helm's Deep or something.
I’m not saying it’s literally a tree. My point is that we need vastly more power to upgrade to the next level of civilization.