I dislike this article whenever it comes up in that it conflates the NSA activity at the site (TITANPOINTE) with the building in a very confusing way. The building is not an NSA building, it is an AT&T building. The NSA is a tenant, along with many other organizations who use the building for meet-me and internet exchange purposes. It's absolutely true that the NSA has a concerning relationship with AT&T that has evidently allowed them to conduct widespread surveillance at telephone switches, but this article seems to be making a case that the building itself is an edifice of the NSA... which is no more true than an Amazon data center.

It is interesting that the building is nuclear-hardened, but it was started in 1969, which was about five years after it became standing policy for AT&T to nuclear-harden all major long-lines facilities. It's not at all unique to this building and is unrelated to the NSA, nuclear-hardened AT&T exchanges can be found from major cities to small towns across the United States (Farmington, New Mexico, for example), and a large portion of surviving microwave relay sites are hardened. The general standard was roughly for a 100KT detonation at five miles, but some facilities were built for more. The motivation was survivable telecommunications after a nuclear attack, which was primarily a requirement of the US Government which relied on AT&T to build out AUTOVON as a survivable C2 and continuity of government system (and AT&T was generously paid for this work). Alongside AUTOVON, AT&T designed and operated systems like ECHO FOX which provided telephone connections to Air Force One and other national emergency command post aircraft. The end-user client here was mainly the POTUS and Strategic Air Command (later Army and Navy components of the triad), not intelligence.

The choice of architect was a fairly simple one, he was, at the time, a notable architect who was friendly with the federal government (who was in part the client due to AUTOVON and other C2 programs, not intelligence) and had prior experience working on hardened facilities like embassies.

It feels like the author chose this rather confusing way of presenting the issue, conflating the physical building with NSA activity that occurs in it, mostly just to weave in the architecture criticism. The building itself is very interesting, but really does nothing to advance the NSA story and rather seems to suggest that the scale of NSA activity is far larger (the whole building!) than it really is (generally thought to be a single suite on one floor, and far from the only suite occupied by staff of AT&T tenants). What the NSA has seems to basically be an office space, cage, and cross-connect agreement, which tons of other tenants also have... the NSA is just unusual in that the cross-connects go to interfaces configured for lawful intercept (which is more a telecom term of art and not a judgment of the legality).