Simplest attack: just make it illegal and prevent people from converting bitcoins into cash. If it isn't connected to the larger economy not many people will be interested in it.
Simplest attack: just make it illegal
Why bother, when they can just use existing laws? Classify bitcoin users as banks, then fine them for violating existing transaction-reporting laws. Tax violations. I'm sure there are dozens if not hundreds of regulations that someone can be charged with.
Not reporting income or profit. Not reporting what you paid to other people that should be counted as their income, and so on. The US seems especially hostile to this sort of thing, what with the number of post-9/11 financial regulations added. I daresay they ...
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