What problem do they have that a blockchain solves? The big win for bitcoin is that the consensus blockchain can be chosen without trust. I would think the military wouldn&#x27;t be worried about manufacturing consensus among untrusted nodes.<p>I guess if the messages are stored in the blockchain, a device would be able to delete the key and other information needed to access the message, effectively deleting the message from the device, protecting the user of the device from having to answer for the content of the message.