Apparently you did not understand technically what
I proposed upthread. We can in theory anonymously (in zero knowledge proofs) prove the tax reporting period totals on our inputs and outputs from transactions we've participated in (but apparently not with Monero's current technology).
While taxes can be assessed and appropriate payment proven, payment of taxes cannot be forced in a decentralized currency that is not controlled by the government. The government can know that person 352 owes x dollars in taxes, but if he doesn't pay it and is anonymous, how can the government do anything about it?
The government cannot prevent anonymous currencies from being used, although it can sanction use of a cryptocurrency. This leaves the possibility of a large underground economy. One possibility is that taxation shifts from income-based to residency-based.