My discussion of this topic in public, circa 1990, was what piqued NSA’s interest in me (and our university security – vs crypto – project). I suspect it was heightened by several facts, not all of which its fair to discuss, even now – being so much about particular personalities rather than topics of science.
It is fair to relate some aspects of then to now, since the context in which research into crypto or security is conducted has changed – with the systemic and subversive aspects of public science policy becoming clearer. Be it then or now, its always useful to look at the social context in which the science experiments into security and crypto are conducted – and note HOW the subversion is instrumented (through people in public positions of authority, obviously). Then only looks at the public/private interface, looking at how public policy recreates its subversion in private enterprises (or communities).
In my case, a confluence of fears made us interesting to NSA – since one of the associates on the project was “rather good” at layer 1 communications, having done 1950-era PhD etc in the topic area – when the core of the module and crypto science was learned – in the secret world of military signals intelligence agencies. NSA may have thought that his excellence in that area was driving our what was actually *not* crypt0 work – since, as Gong points out well – the world of layer 1 modulation and the world of crypto are two sides of the same coin.