OF the choices of items/inventions listed, I’m going to go on the offensive side and say the MP40.
The Arisaka was a fair-to-decent weapon (I’ve owned my share of them) for it’s time,…but it was the absolute wrong weapon for attacking and counterattacking in a short-range action, especially in situation where banzai attacks are being employed as the Japanese made use of them historically: one shot on the run and then lead with the admittedly wickedly-long bayonet into a fixed, well-entrenched, and desperately-determined defensive line fielding weapons with much higher rates of fire, not to mention quality. Now, consider re-arming those banzai waves on Guadalcanal, etc with a submachine gun far superior to their own examples (of which much fewer were actually employed by Japanese forces), and when the action gets close, the balance of firepower becomes much less unbalanced…perhaps enough to carry the day somewhere along the line. Would such a change have averted the eventual outcome of the war as happened? No, it is far too likely that they still would have lost eventually any way, but with such increased firepower being widely employed, their mass-attack tactics would’ve been more effective in inflicting higher casualties…something that had already begun to wear heavily on morale amongst both the public and the troops themselves as the war dragged on. The A-Bombs themselves were used specifically because (at least in part) the high command and the gov’t didn’t believe the public would stand for the horrific casualty numbers they expected to suffer during an invasion of the mainland. Now, just imagine battles like Guadalcanal, Peleliu, Okinawa and Peleliu where the MP40 could’ve been employed to its fullest advantage in large quantities during quick, violent short-ranged actions in the jungle and across all of that rough terrain. And their actions against the British and Australians during the New Guinea campaign would’ve been more effective in that similar terrain, too. It’s a much bloodier scenario for Allied forces.
If i had a 2nd choice I might have gone with ‘other’…and chosen German defensive doctrine. Yes, they lost, but they were very very good in defensive warfare…much more so than the Japanese imho. I think the Japanese wasted a ton of time, resources, and initiative during the island hopping campaign and i firmly believe that the Germans would’ve been more effective in that role if one were able to swap the two. The Germans were very effective in counter-attack and retaking the initiative from defensive to offensive momentum, two things that I believe history shows the Japanese were not effective at.
Rob.
