Should the United States be split into smaller localized manageable regions?
I would argue yes, personally.
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it is?
It is, but on a federal level I think it still needs to be split up into multiple regions. I.e. the north-east, south-west, etc. Choosing to subdivide further at a state level would be optional.
Yes. China is actually a multi-race country. Their culture is diverse.
Xi and China's party enjoy the power that comes with control and unity. Heck China doesn't like the Mainland, Hong Kong, Taiwan, and the South China Sea being 4 distinct areas. Other nations might be fearing China now that it has grown rapidly from 1T GDP to 13T GDP. Other nations don't really have an influence on whether China will split into smaller regions quite like how China has an influence on whether international corporate lobbiests will try to lobby (successfully or unsuccessfuly) for Trump's impeachment.