It's still make sense though. In 1943, The German manage to create a new enigma signal that confuse the intelligence service of the allies and manage to cause a communication chaos during the Battle of Kasserine pass. (They manage to break it again in July of the same year, just before Operation Husky.) Assuming that most of the Allied intel base have been destroyed. The new enigma code system + Ineffective Allied intelligence is pretty beneficial to the Japanese.
God, I HATED this mission! I only ever beat it ONCE to unlock Road To Hawaii, and I NEVER beat it again afterwards. It had to have taken Me at least two dozen Mission Failed screens before I finally fucking beat it. And that was ONLY because I got lucky with the Torpedo Spamming with the Auto-Loader on the I-400. By then is when I noticed it avaliable for use under Naval Supplies. I think I got it from getting the Hidden Objective: Sink at least one ship from the Supply Convoy with Both Subs. It was just under minute after the cutscene signaling the arrival of the ASW Convoy. Sank the designated targets; Escort Carrier. And the 3 ASW Destroyers. AND on top of that, got lucky with the 2 Secondary Destroyers for The Gold.The Carrier ended up going down last.