Decentralization on its own isn't the answer either. Look at what happened in USA after the Civil War. Progress was gradually erased on the state and town leve

Decentralization on its own isn't the answer either. Look at what happened in USA after the Civil War. Progress was gradually erased on the state and town level. "States' rights" became a fig leaf for oppression of former slaves. The Constitution guaranteed them equal human rights, but reality was something different because the federal government gave up. It's hard to believe that this lasted until the 1960s.