The biggest factor creating centralized power isn’t understood by most of the people, and damn few politicians apparently. That is the monopoly authority of the Congress to create the currency. States are net “users” of currency, just as you and I are, and therefor must remove currency from the private sector via taxation before it can spend. This means that big initiatives and needs all states have in common are best financed by the issuer of the fiat currency. Even if you assume taxes fund government at the federal level (they don’t) the efficiency of scale makes it more logical to fund such spending at the highest level, discounting any political impact on the same, and making benefits of that spending universal to all states, regardless of their population or resources.