https://en.wikipedia.org/wiki/United_States_Department_of_De...
Stoping and questioning why somebody uses DoD or DoW is way more telling than using any of those. Especially that both are perfectly fine, even officially.
A square was renamed in my home city about 20 years ago. We still use the original one usually, even teens know that name. I use a form of the original name of our main stadium which was renamed almost 30 years ago. Heck, some people use names of streets which are not official for almost 40 years now. Btw, the same with departments of the government. Nobody follows how they called at the moment, because nobody really cares. That’s the strange when somebody cares.
Or it could have just been a genuine question. I'm not American and I've seen DoW used in newspapers and thought the name change was official. Personally I've thought it a more apt and honest name for what they do.
But the backlash in the commments here show how ideologically charged the question seem to be.