There is a difference between owning bitcoin and owning a claim on bitcoin, and most people who think they hold it, are holding the claim. Their coins sit with an exchange, a broker or a fund. What they actually have is an entry in someone else’s ledger and a promise that they can get to it. Most of the time that promise holds. The trouble is what happens on the days it does not, and how little say you have when that day comes. We saw a version of this across Europe over the summer. When the EU’s new crypto …