Who holds the per device key? If someone holds all the per device keys (or parts of the per device key) you've painted a bulls eye on their face. In all honesty

Who holds the per device key? If someone holds all the per device keys (or parts of the per device key) you've painted a bulls eye on their face. In all honesty, I cannot trust the US government with secrets like this because I don't see us being willing to secure it at the same level that we secure our nukes. And dear lord even that level of security likely won't be enough to fend off internal and external threats.