The Japanese were a more dangerous enemy than people living today can even imagine. If they had caught our aircraft carriers in Pearl Harbour in 1941 we would all be speaking Japanese and German today.
I hope you're being sarcastic.
No. The Japanese would have surrendered to the US in 1947, instead of 1945. More American Baby Boomers would not be here, but that's about it. The Japanese did not want the US, they wanted a free rein in Asia. The Chinese and the Koreans might be speaking Japanese, but not Americans.