I would imagine the money to reimburse the poor would come from the sales tax itself.
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Well, take the UK, so its all in GBP
1.1 Trillion borrowing.
5.3 trillion off the books debts. Primarily pensions, and just for the pensions where people have paid up front, (not pensions resulting from future payments), or pensions associated with people who have worked for the government - deferred pay.
The rest is PFI, which is debt deliberately maniplated off the books. Plus expected losses on guarantees, and nuclear decommissiong where the companies paid up front, for the government to undertake the work.
About 7 trillion in total.
Taxes at 550 bn a year. 0.55 trillion.
Government spending at 0.7 trillion
The current position is unsusbtainable. They are bust.
So whose is going to lose.
1. People dependent on the state. That's the poor, who receive redistributions of money, primarily because they are taxed too much to live off what they are allowed to keep.
2. People forced to save with the state for their pensions. That's ex state workers, and the poor again. They haven't enough to live off, yet they are still taxed for that pension. It pays out about 20% of the value of payments. The rest has been redistributed, or spent on other things.
Since that's a pretty unpleasant cocktail, the state will try and tax its way out. That won't work. The UK has lost 10,000 out of the 16,000 million a year earners in one year. France is haemoraging the wealthy because it said, we will tax you at 75% on income, then welfare on the rest, and a wealth tax to boot.
Remember, the EU says freedom of movement of people, goods, services and capital. You would have to derogate from the treaties to prevent capital flight. ie. The politicians of the country would have to say, we won't allow you to leave unless you hand over your money. It can be done legally, but it reeks of the third reich.