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Despite of probably having an overly broad question and a simplistic view: Everytime I read about the British politics these days, I wonder, what is all the fuss about Brexit about?
They had a vote, and the people voted for "leave". The UK, as every other current EU member, once was not. Why don't they just leave?
About the backstop: Why do they not just put in place what was before the EU membership?
About the deal: UK was maybe one of the most global trading nations, why do they not continue/start again with this?
I am from Switzerland, which is not part of the EU, and we still have a government and food (and many trucks ;-) too), so I can hardly see nation-dividing problem here.