Bitcoin and positive vs. normative economics
Krugman is to Bitcoin as Ebert was to video games.The central failure of Krugman's understanding of cryptocurrencies is in the value of mining. It's not simply throwing energy away into solving useless math problems; it's spending energy to create infrastructure. That infrastructure is the part that does have intrinsic value, that can be used for something else in the same way gold can be made into useful things. Look at Bitmessage or any of the other projects built on top of Bitcoin. These form the floor Krugman can't seem to find.