NSA has several guides on degaussing and demagnetization of media
However, not likely to disclose the very best and latest about anything, but
will provide, like GCHQ and others, guidance on "information assurance"
through university partners, contractors, conferences, hearings, study
commissions, web sites, blogs, dual-hatted comsec experts, ex-officials
now in business, unauthorized disclosures such as Snowden's and Manning's,
and the industry of dumbfounding, tail-chasing, redacted, cherry-picked FOIAs.
The Internet will never be degaussed, much less highly magnetized and gaussed
IoT, Wayback, secure drops, searches, mail lists, the sun, sea and sand.