Buying a stock or Bitcoin is not taxable. Selling an appreciated stock or asset is taxable. If you bought 100 Bitcoin for $900 each in January and sell it for $9000 each in December, you owe the federal government 39.6% x ($9000 - $900) * 100 bitcoins
Sure, it's exactly what we're talking about. The IRS says less than 1000 citizens claimed Bitcoin appreciated capital gains, but Coinbase has 14,355 US citizens who transacted more than $20k. Surely there are a few thousand people in there not reporting their appreciated gains from Bitcoin sales.
