I would hypothesize that cash transactions -- at least peer to peer transactions -- in general do not get taxed. It's axiomatic that cryptocurrency transaction

I would hypothesize that cash transactions -- at least peer to peer transactions -- in general do not get taxed. It's axiomatic that cryptocurrency transactions are rarely taxed, most people have not paid taxes on those transactions. The IRS is certainly trying to tax them, and the electronic ledger function of (some) cryptocurrencies will make it easier to track them under some circumstances than cash. That may change as time goes on -- I'm not sure enough how libra is implemented to have an opinion on that yet.