Note that shutting them down would dump us directly into full
MAGA. Why? Because all inflation comes from the FED's creation of new money through loans - which are not really loans, but are creations of new money. And the government is the biggest borrower from the FED.
As for IRS taxes, taxes collected determine the amount of money the FED can loan to the government. No FED = no IRS taxation. The whole money operation would have to go back under the US Treasury, under the Constitution rules where money is based on gold and silver. We would be back on the G and S system.
There would be an adjustment period, which would include changes in international trade. We would have to make a whole bunch of our own products for ourselves again. Tariff reduction might be absolutely necessary until we got our production cranking again.
Lots of things would change, because we wouldn't be leaching off other countries in some ways. And they wouldn't be leaching off us in other ways. It might be the best time for Russia or China to attack and destroy us. But if they didn't, it would be the best time for equity among nations.
The one bad thing is that all the money the FED has stolen through taxation (IRS) and inflation over the last hundred years, might totally be lost to us if we didn't go to war with Europe, because the FED is owned by European money-mongers.
Think of the changes that might come to the Forex (currently trading over $5-trillion a day).
