The theory is actually that some people have standards, some people just want to advance, and in the long run the latter will inevitably dominate the organization.
Meanwhile...the US Army's Public Affair Dept. is headed by a 2-star general (same rank as the top general in command of an entire Army Division), and its mission is:
"Public affairs fulfills the Army's obligation to keep the American people and the Army informed, and helps to establish the conditions that lead to confidence in America's Army and its readiness to conduct operations in peacetime, conflict and war."
(Source: https://www.army.mil/publicaffairs/ I'd guess that the Navy, Air Force, etc. all have similar...)
This kind of statement assumes a too simple model of the involved actors.