The core argument is that digital payment systems can fail very easily during times of "crises or war". This is because typical digital payment systems by design only work if the devices are connected to the internet. Moreover, credit mostly only works if you get permission from one of two foreign companies.<p>The question I have is, can you design a digital currency that works without the internet?<p>The way bitcoin and friends work is that you prevent the double spend problem by announcing the transaction on the network and waiting enough time that it becomes computationally infeasible to reverse the transaction.<p>However, can you design a hardware device, with some sort of security enclave, using which when the private key corresponding to some coins are transferred from the sender to receiver, the receiver can confirm that the keys have indeed been deleted by the sender.<p>Obviously, a look-alike device with a fake enclave can be built to scam someone. But if the practical difficulty of creating such a device is more than the difficulty of printing fake cash, then you can use such a digital currency.
The way I see it, when I carry cash and use it for transactions, there's at most a a few dozen people physically close enough to me to even try to exploit the transaction, and the most they could capture is the cash I have on hand. Chances are, if I dropped a wad of cash, they'd pick it up and hand it to me. Sure, it's easy to rob someone, but the chances of me being around someone that would even want to try is near zero, and the repercussions are significant.<p>When I make an electronic transaction, there's tens to hundreds of millions, if not billions of people that could attempt to exploit the transaction. Despite it being significantly more difficult, the chances of one of them trying and succeeding are still much greater, and they can take far more.