Did you notice the "compared to" part of that? I have read about a dozen books on the subject and not simply the sources that would have been approved during the McCarthy witch hunt. The US contribution to bringing down the NAZIs was a drop in the bucket compared to what the Red Army fought. Also, US financial and oil interests were in many ways helpful to Germany. Please be careful not to just respond to part of an argument, there is always more than one premise to any conclusion. Yes, even D-Day, that highly propagandized and romanticized battle that has been overly glorified was but a skirmish in comparison with the Eastern Front.