Security as a public health discipline, not an engineering one

Sorry @MarjaE. I’m not changing it, since I’ve seen the “an” variant far more often from English majors in formal writing than the “a” variant from them. And I trust English majors to know how English works better than I do.

Does anyone have comments on the message of my post rather than the fairly intelligible mechanics of its linguistics?

I’m fixing for a good argument/debate. Either one works.