How WOULD we collect taxes without some type of department. Honest question; not trying to be funny.
Have the states collect the taxes and send it to the Treasury department.
How did they do it before the civil war?
Anyway, the way to do it easy: Using an electronic payment method you take a percentage from each “receiver” and forward it to a third party. You can do this at the source or at the bank. That third party would be the IRS.
Yes, I know that would be a very unpopular decision and process. But you asked how we COULD do it. It would take a programmer about a day to make it work.
Ever wonder why they are going for a cashless society?
We would all pay a sales tax and the states would transfer funds to the Federal gov’t.