Greetings @bobreedo. Thanks for your response.
As far as barter goes, yes, governments can make Bitcoin illegal. Will they? Probably not. It isn't necessary. All they need to do is make it highly unattractive and the vast majority of users will walk away. If cryptocurrency speculators are handed very large financial losses, over and over, for a period of years, they will tap out.
Here is a thought experiment: would you invest $10,000 in Bitcoin today if you were pretty sure that the US Fed and Chinese Central bank were going to hit it with a full assault?
The bottom line is this: if they want, almost any central bank of any decent sized country could absolutely steamroll Bitcoin if they really felt like it. They could make it rain sell orders and the rain wouldn't stop. Given this reality, do you really believe that none of them are going to do it? Do you really think they are going to let their grip on power simply slip through their fingers?
RE: Why Cryptocurrencies will fail… eventually.