I am comparing the official missions of the Stasi and NSA which are significantly different.

If your argument is that the NSA is not acting in accordance to its mission, or that abuses are taking place, or that the NSA is acting like the Stasi that's something else entirely, completely separate to what I'm discussing.

I'm pointing out that these are different agencies with different roles and responsibilities, and trying to draw parallels between an NSA data center and a Stasi archive is not really useful.