> same as the english. militarily the luftwaffe wasn't going to defeat the raf, but the raf would not been able to do anything for morale if the population is starving. without american and canadian foodstuffs involvement there's a fair chance they would have had civilians in an uproar demanding a ceasefire with how poorly rationing was going. ration books continuing into the mid 50s gives you some idea of how much worse it could have been.
United States