Really? How many bullets did China produce for the European theater? Artillery shells? Warships and planes? How much food and oil did they ship?

More Chinese people died. By any other measure the United States won the war via the Lend/Lease program.

Mao's entire army was outfitted with American weapons & vehicles in WWII which they then used to run Chiang Kai-shek out of the country to what is now Taiwan. We were initially going to arm Chiang Kai-shek but he was refusing to use the arms against the Japanese, believing he would need them for the civil war that would follow.

Interesting snippet of history.

America then sent us the bill, the UK didn't finish paying it until this century.

and ?

How about this for a counterfactual: if not for China, the Japanese would have seized India, and from there raise hell in Iran (oil supplies!) and put serious pressure on the Suez Canal.

China was involved in the Pacific theater, not Europe. What are you referring to?

China had nothing to do with the European theatre. US military and economic assistance was critical to pushing back Nazi Germany forces into unconditional surrender. Meanwhile China had no part in it whatsoever. Critical versus zero, seems pretty clear, how did you make this massive mistake?

Even in the Pacific theatre, the US Navy was absolutely critical to collapsing Japan's empire.