I am afraid there are many historical examples in which countries clearly understood they were the attackers. Germans will recognise that Hitler attacked Poland. I am not going to dig into Vikings, Mongols, Huns, Romans and others that were perfectly conscious of being on the offensive.
If Axis won WW2, you would only hear narrative about them defending...same as Americans today don't say "we did war crime by dropping
two A-bombs on civilians" but you hear "we did it to prevent loss of life by both USA soldiers and Japan civilians and soldiers"
Also, Romans were spreading democracy and culture to barbarians
Romans sometimes did use subterfuges, but I think that they kind of saw themselves as a military superpower, without any particularly high reason to invade others - the moral concepts of the time were not about peace or understanding - rather the opposite - so they were absolutely fine with waging aggression. To be honest, most of the times either they invaded others or other would invade - it was a very different world in some ways, states and countries were not as established.
As for the Nazi Germany, the narrative at the time, uncensored by the winners, was effectively conquering the lebensraum on the basis of being a superior race. I think they had a clear idea of what they were doing.