What about them? These technologies already existed, the only thing that changed is that economies of scale enabled by the centralized power. Smaller tribes and villages could have gone by implementing more localized solutions.

Until local interests conflict. Consider the perennial angst over water rights in the American West…

Local conflicts do not get solved by higher levels, they get tapered over. WIth all the power and resources amassed by the Federal Government, one would think this could've been solved already, right?