They don’t need to make it illegal... just treat it as a commodity and tax the hell out of it as a barter exchange. Also, force people to keep accurate records of all transactions, which defeats the anonymous transaction feature.
The record "keeping" isn't an issue, since it's all electronic. Moving it over to a tax app, might be a lot work tho. Anonymity never was a strong feature, even from its creation.
This will be burdensome for the little miner guys working out of their homes, unless this first guidance is greatly amended. They are also the ones that process the transactions.
I see someone building an app that will take all of the transaction data, pull in the historical price records (that's brings up another question: the price of record for determining value), and offer the ability to export all a your tax filing software!
"tax the hell out of it "
"force people to keep accurate records of all transactions"
Do you work for the IRS? If not; I'm sure they would love to hire you!