Irrelevant (Score 2)

All of this is irrelevant as literally all of the hardware (everything from cpu to the last tiny chip controlling your keyboard, secure enclave, ...) and most of the software (bios-layer, operating system, anything lurking around hidden and equipped with root rights, ...) on all of the systems you use (PC, mobile phone, ...) is under control of the adversary. After the lessons of WW2 information warfare (Enigma and the like) you wouldn't think that any government allowed their potential enemies to equip themselves with mass produced $10 devices capable of encryption out of their reach, would you? A modern pen-and-paper encryption (and protocol)? That would be something to consider.