As I commented on the youjo senki movie, if there's any individual other than Degurechaff that's responsible for her extreme rapid rise and influence on the war situation, it would be Anson Sue.
Imagine, if they hadn't attacked Tanya in Norden ?
She would've remained an artillery observer. Possibly getting a regular promotion down the line, but a) She wouldn't have gotten THE MEDAL and b) She wouldn't have been part of the newspaper and noticed by Dr Schugel for his experiments, thus giving her the Type 95.
Anson Sue is responsible for that in a way. By his orders to eliminate her to save his men from artillery bombardment, he unknowingly let loose something that would doom his nation later on and maybe other people.
Then , Anson was also part of the invading soldiers, so he was part of the troops starting the whole conflict which lead to his death.
True, he might not have been able to change anything about that, but he was still part of it.