Comment by dragonwriter
4 hours ago
> It was always called the Department of War [1] from 1789 until 1947.
No, what became the Department of Defense didn't exist from 1789 until 1947. The cabinet level Department of the Navy (current Department of the Navy) and the cabinet-level Department of War (later split into the current Department of the Army and Department of the Air Force) did, as separate, co-equal entities with no single civilian head over them beneath the President.
The National Military Establishment under the cabinet-level Secretary of Defense was created as a unified military structure in 1947 over both the Department of the Navy (which remained a cabinet-level department) and what had been the Department of War (which was split into the cabinet-level Departments of the Army and the Air Force). And in 1949 the three service departments were fully subordinated within the NME instead of being cabinet level, and the NME was renamed the Department of Defense (pribably not entirely because it was really awkward having the combined military organization use an initialism that sounded like “enemy”, but...)
More detailed version in https://news.ycombinator.com/item?id=46825849
All you are describing is a restructuring of which the Department of War had gone through repeatedly throughout its history. It's not like it had the same structure, or anything remotely like it, in 1942 as in 1789. The choice of the name was, as you observe, a choice. And it coincides exactly with the move away from public honesty in international relations and events.
You have things like WW1 being framed (at the time) as 'The War to End All Wars' but I think that was probably naivete whereas after we started calling war 'defense' we entered into the era of 'police actions' instead of wars, like the Korean War, and outright false flags such as the Gulf of Tonkin Incident for Vietnam. All the while the CIA was running around acting like a rabid chimp all across the world. It was entering into an era where deceiving the public became standard operating procedure, of which framing war as defense was but one typical aspect.
I believe we are now leaving that era, and I think that is a good thing for everybody.