The fundamental problem is that any extreme supremacy only lasts for 1 era.. if you don't continuously improve and reform you can only coast on reputation for so long.
The Spanish conquered Aztecs and Inca once in 1500s. Then the rest were immunized and it took industrialization (and the resulting huge population advantage), railroads and automatic cannon to take out iron age hunter gatherer horse archers in the American west in 1800s.
China lost once, to steam power, in 1840s. But then was able to resist Japan with heavy internal combustion engines, tanks and planes with early industrial age tech like bolt action rifles and explosives.
Diffusion of technology and ideas guarantees this. And with the internet, lessons learned filter down in months, not decades.
The Spanish conquered Aztecs and Inca once in 1500s. Then the rest were immunized and it took industrialization (and the resulting huge population advantage), railroads and automatic cannon to take out iron age hunter gatherer horse archers in the American west in 1800s.
China lost once, to steam power, in 1840s. But then was able to resist Japan with heavy internal combustion engines, tanks and planes with early industrial age tech like bolt action rifles and explosives.
Diffusion of technology and ideas guarantees this. And with the internet, lessons learned filter down in months, not decades.