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.
NRA Life Member
Me: "The .45 GAP was an answer to the question nobody asked."
Trooper pal: "Says the guy who thinks .38 Super and 10mm are viable pistol calibers and gets mad when Wal-Mart doesn't have them."