Local wars here and there happened and will happen in the future. There's nothing special about Ukraine or Taiwan in that regard.
World will move from US-centric model to multi-polar model. One pole is China, one pole is Russia, one pole is EU, one pole is US, one pole is Iran. Confused about India but probably it'll be a separate pole as well. Probably there will be African pole and South-American pole. Economy, Internet, Science will be divided among those poles. Some poles will cooperate, some poles will not. Countries will join some pole or dive into anarchy. That's the script for next 50-100 years, then another country will rise as a world hegemon. I expect it to be China, but I might be wrong.