No aid from US

What If the United States didn't become involved in the war? How would this effect events such as D-day and others?

 

WOW that opens ALOT of what ifs!
Well...i tend to think that Britian by herself could not invade and liberate France. Britian would have continued her night bombings but i think the Luftwaffa would have been more prevelant than it was historiclly...for obvious reasons such as...less factory production would have been damaged...less pilots would have been lost...less fighters would be needed to defend germany itself...i think basiclly germany and britian would have continued a bombing campaign against each other...france would have never been invaded...maybe Holland but i dunno. Italy may still have been invaded...and the germans would still have lost North Africa.
So basiclly i see and large air campagn against britian...and a british night campaign against germany.
So no large invasion of france...maybe fighting in Holland...and maybe fighting in Italy. I think that by the time the Russians captured Berlin...the British would not have any major units fighting in germany. And the country that basicly won the war would have been Russia...with britian as an aid.
I bet during the surrender terms the USSR would have gottn ALL of berlin...as well as all of germany.

 

So in conclusion, Germany and the Nazi cause would still have lost the war? Not quite sure what the outcome of this estimate is.

 

Depends on the parameters of "not involved".

If we did absolutelynothing (ie no lend lease. nada.) it may be that Germany would have actually won...
Of course, this presumes that Russia could not have held on without US aid, and that could open a whole new "what if".
I myself don't believe that Britain would have managed without American assistance either. Recall that we were also helping them with "stuff" before we actually got any combat troops into it, and before our 1000 plane raids were making their night raids look like firecracker-tossing...
As to the war in the East...
Presuming the same outcome for the opening months of Barbarossa, picture the bulk of the troops allocated to the Atlantic wall being sent East, as well as those who either were stationed in Italy, or transferred there after the Allied invasion, which I do not feel could have been done without America helping the Brits toss DAK out of Africa. (true, DAK was being somewhat bested by the Brits as time wore on, but how much of Monty's big build-up was American materiel?)

What's to be done about such matters as British naval superiority (another use for all those U-boats, perhaps) and Russian fanatical tenacity are other matters.
If historical accounts can be believed, Russia was at the bottom of her manpower barrel at the actual war's end. If the Wermacht could have put a million or more men on the Eastfront...
Without American bombers to battle, could the Luftwaffe have gotten its collective ass in gear and built strategic bombers that could have hit British naval assets in port?
Question...questions...questions...