Part of the problem that the US Navy ran into when it went to war was that – like many military forces before or since – it had to learn some things for itself before it believed them. The British had over two years of experience fighting the Battle of the Atlantic at that point, but the Americans didn’t feel that they needed any advice from them on the matter. It didn’t help that Admiral Ernest J. King was an Anglophobe, in addition to having a generally abrasive personality. (His wife reputedly once said: “Ernie is the most even-tempered man I’ve ever met. He’s always in a foul mood.”) As a result, the Americans made mistakes in their early ASW methods of operations which could have been avoided. In fairness, the US Army had similar learning-curve problems in North Africa, notably at Kasserine Pass if I remember correctly.
