Well, if you're a defense contractor you have to tell your secrets to the government. But if you're the government you don't have to tell your secrets to a defense contractor. This asymmetry means the government can operate substandard systems indefinitely, and only be found out during war by the enemy. Musk, otoh, needs to develop an actual secure system and that's much harder. It needs to be open source style crypto secure since you're sharing so much operating info. Can it be done? Will secretive nations win the century, or will those who work somewhat adversarialy (not too much though) with private industry to develop truly secure systems come out on top?