You said it Mark !! Before the US came into the War we had already
turned the retreat of an ill-equiped hastily prepared British
expiditionary force at Dunkirk (an unprecedented feat in itself), into
the defeat of Hitler's best at El Alamein. Destroying the Italian army
on the way........with distractions on other fronts, like the Japanese!
Likewise the US turned the defeat of it's Pacific Fleet at 'Pearl
Harbour', into the victory at 'Midway'.
regards
Colin