I'm not sure the analogy is so bad, to be honest. The USN submarine force was extremely successful in the Pacific... eventually. But they went to war with pre-

I'm not sure the analogy is so bad, to be honest. The USN submarine force was extremely successful in the Pacific... eventually. But they went to war with pre-war submarine designs, and used a strategy of pumping out the same old submarine types, with only minor improvements as the war went on. It wasn't until the end of WWII and the start of the Cold War that the US started to integrate features from the Type XXI and really try to push the state of the art of submarine technology. But the point is that the Gato and Balao-class submarines were good enough for what the USN was doing, the important thing was actually getting the boats out to the theater of war. An advanced upgrade project would have risked the ability to do that at the very time such risk was unaccepted. That was Germany's problem as explained in the article: Even with the assuredly-better Type XXI submarine, Germany would still need many other things to go right to prosecute an interdiction war. It would have needed command and control improvements to account for the submarines being submerged more often (especially if they wanted to use the effective "wolf pack" tactics), better maritime reconnaissance to find convoys in the first place, etc. Its sonar would have been useful, but the flipside to that is that Allied sonar and ASDIC would also have been useful (defeating ASDIC was one of the reasons German U-boats operated on the surface in the first place). In short, the Type XXI really did counter a lot of the Allied advancements in antisubmarine warfare, but it still would not have been enough. Those resources could have been profitably employed elsewhere, perhaps in other new weapons development projects. On the other hand, aviation represented an area where new development was instrumental (and cost-effective) throughout the war. The German jet fighters would have been very dangerous if they could have worked them into their Luftflottes sooner.