Since this warfare clearly has a spiritual side, it would stand to reason there is more than one "Keystone". In the Bible, there are two "Christ's", although one is the true Christ, and the other, a counterfeit, the AntiChrist.
I've recently heard an argument that this could be a similar case with the "Keystone" that Q refers to. I came to the conclusion this could be true because I'm familiar with Scripture and had the thought process above.
I've seen OldFags railing NewFags for exploring the Keystone Theory, because they are discussing opinion different than what Q has said the Keystone is,
(No Such Agency + POTUS + USMIL), but the likelyhood of there being a counterfeit seems like a good theory.
The argument of "two" Keystones suggested the Senior Executive Service (SES) could be their keystone. AS I pulled up the emblem of the SES, I wasn't surprised to see they use a Keystone as the symbology on their emblem and flag.
I'm not terribly familiar with the SES but this theory seems plausable.
https://en.wikipedia.org/wiki/Senior_Executive_Service_(United_States)
https://www.opm.gov/policy-data-oversight/senior-executive-service/
https://www.opm.gov/policy-data-oversight/senior-executive-service/overview-history/
THen, I looked at the home page of the DOD, the emblem in the top left corner is none other than a KEYSTONE. I have to admit, I was floored! Q's told us there are no coincidences. https://www.defense.gov/
https://www.nsa.gov/