No, that’s an entirely valid point and I even suggest you were in error when you conceded. If two individuals have enough private mutual information theory allows them encryption that can not be cracked.
A one-time pad has to be transmitted, too. MITM will crack it.
A one-time pad that needs to be transmitted can be violated by MITM. But if the relevant private mutual information is already shared or is shared directly without encryption then the encryption they use to communicate is not (in theory required to be) crackable. Since the claim was that “all encryption can be cracked in theory” it is not enough for some cases to be crackable, all must be.
Is it too pedantic to mention one-time pads?
No, that’s an entirely valid point and I even suggest you were in error when you conceded. If two individuals have enough private mutual information theory allows them encryption that can not be cracked.
A one-time pad has to be transmitted, too. MITM will crack it.
A one-time pad that needs to be transmitted can be violated by MITM. But if the relevant private mutual information is already shared or is shared directly without encryption then the encryption they use to communicate is not (in theory required to be) crackable. Since the claim was that “all encryption can be cracked in theory” it is not enough for some cases to be crackable, all must be.
Fair enough—I was out-pedanted!