Some cities are important in every category though, just by virtue of concentrating a lot of the population. For instance the US would be pretty much in complet

Some cities are important in every category though, just by virtue of concentrating a lot of the population. For instance the US would be pretty much in complete disarray for decades if the coastal cities of California and the East Coast were just wiped. They concentrate a lot of the power in every single respect, and also the brains.