It's particularly irate because tradition is a finicky thing that means whatever to whoever is arguing wants it to be. Go far back enough and Russia was a Viking kingdom ruled from Kiev. So Russia traditionally belongs to Ukraine. Checkmate, enlightened faux-academics.
IMO, it's often not even "war bad" but "fighting bad". Thus wanting the defender not to defend because that would be just as bad as attacking.
I consider myself a pacifist, so I prefer peaceful and diplomatic ways before going to war. But if you are attacked, you have the right, if not the duty, to defend yourself and your citizens.
Reading your edit not gave me the mental image of a country being attacked and their military just surrounds and protects one singular confused random citizen
We tend to think of the aggressor when we say war is bad. It makes sense, they're the ones who initiate the conflict and make the war exist.
Defending yourself in a war though is, well, defensible. Being anti war can never be an absolutist position. Otherwise, those who are fine with war only need threaten war to get what they want. Do you truly live in peace if it's because you give the aggressor everything they want? I'd argue no.