People start thinking euthanasia might be a good idea. Disease is eradicated, and everyone limits families and consumption, leading to a happier and fairer world. They lick cancer and heart disease, only to be hit by new diseases and syndromes, plus old ones where the medicines not longer work. Nano-technology produces miniature machines and wonderful new materials and manufacturing techniques. Nano-technology is made to work, but it's prohibitively expensive and unreliable, and is dropped.
Money continues to be the most important thing in people's lives.
Money gets abolished. Look - admit it. Europe becomes Top Group of Nations. Some other country you've never thought of becomes Top Nation, say in Africa or South America. Nations get abolished.