In the digital age it is not clear how these can be authenticated. Source verification, timings, ostensible authors, channels of propagation - all seem murky. 80 years ago when this was written they'd be fairly self-evident or hard to cover up.

One of the things we learned from Snowden which has made nonsense of incident forensics and malware analysis ever since is the existence and application of "attribution engineering toolkits". Many modern attacks seek not to disrupt the ostensible victim so much as to point the finger at the desired culprit (actual target), amplifying the attack by provoking a response.

It's clear that we need new forms of epistemology and intelligence thinking.