Stalingrad. The Germans got so swept up in conquering a city of little strategic importance that their eventual defeat there may have well cost them the war despite making headway throughout the rest of Russia. That's what we're doing arguing about stuff like this.
I was thinking the IJN off of Guadacanal, but I see your point.
"Growing up as both a Southern and the son of a child of the '50s, I was imprinted with several things that have long stuck with me. The F-86 Saber Jet was the finest fighter ever flown, the National League is always superior, and Leslie Coffelt
was the finest revovler shooter since Mr. Ed."