Billionaire technology investor Peter Thiel thinks bitcoin has a problem: The government won’t shoot you for it.

In a recent interview on website Vox, Mr. Thiel linked the value of money to the requirement that taxes be paid in the government’s currency. “You will not be able to pay your taxes in bitcoin. You have to pay them in dollars. If you don’t pay them with dollars, there will be people who will show up with guns to make you pay them,” Mr. Thiel said.

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