[Karl-Heinz Jaeger]

Yup, the Doughboy style helmets were in use at the start of the war, along with M1903 Springfield rifle which was gradually being phased out since the M1 Garands inception in 1936. I've heard it said that the poor chaps captured during the early days and held in the Japanese prison camps didn't recognise the US soldiers who came to liberate them in '44-'45, since they had much different equipment, and were much better trained and organised.