TDPerk wrote:" It is worth a mention that the US military entered WWII with some sectors of its tech in really backwards condition "
And some was superlative. The "any gun within range" artillery directing system was a terrible shock to the Germans, as was later the radar fuzed air-burst ammunition.
Dad's specialty was calculating Time on Target. Then they gave his unit two dozen Pozit fuses and that was a sad day for some Germans in Duren. I've written that episode up a couple of times here. But those came late ... Dec 1944 was when they were first used with field artillery. More of them were used for antiaircraft fire, where they apparently increased effectiveness about 5 x over conventional fuses.
The Army did upgrade their howitzers shortly before the war. The new models were excellent, but more importantly, they ditched the horses and pulled them with motor vehicles. My dad's unit, the 967th FA, was one of only a couple of units that pulled their 155's with tracked vehicles.
They approached the war pathetically under-manned and under-equipped, but got production and recruitment rolling fast. The National Guard was pulled in to the regular military in the year preceding Pearl Harbor ... that's what precipitated dad getting promoted 2 ranks and shipped off to Fort Sill to Battery Officer Course.