Decentralisation is under way not only through political devolution, but also through privatisation and the hiving-off of regulatory functions to autonomous bodies. Because military strength was one of the justifications for the creation of larger states, a less militarised Europe might eventually see the re-emergence of a medieval patchwork of small states. Perhaps the absence of war is also one of the things behind the falling prestige of government and politics. Now that we no longer need the state to defend us, we do not conceal our dislike of it taking our money and ordering us around. We impeach presidents and hound cabinet ministers.
War needs leaders.
Out of war come kings and dictators. Peace is republican. The era of great men is behind us. As the state weakens, so does the nation. As Ernest Renan said, the nation is bound together by the memory of sacrifices made in the past and the readiness to renew those sacrifices in the future.