While I have no doubt that officer (and even most NCO) do know more than basic english, I have some doubts regarding the typical high-school drop out who enlists in the infantry.
So if you need to talk about geopolitic, aircraft maintenance or even coordinates two different group of soldier, NATO english would be fine. But how would a multi-lingual crew works on a warship ? What about a multi-lingual patrol ?
What the hell? And how didn’t it ended in a massive lawsuit?