i just made this diagram by comparing history of the US with possible future history of mars (timescale included). notable technological turning points include:

• solar panel production on-site, because it would mean that the settlement has very large amount of energy available, and just like the steam engine and all the heavily-motorized machines kicked off the industrial revolution, having much energy available would do a lot.
• polar ice extraction because water is just extremely valuable, and therefore it’s worth it at some point to build that 3000 km railway system to the korolev crater. this would flood the economy with water which would give another important growth spurt.