#1 The B17 really sucked. The Mosquito could have done a much better job. But that’s war business.
#2 The Japanese’s fate was sealed after Coral Sea and Midway. They didn’t have a ghosts chance in hell. They were just stubborn little bastards.
The Japanese recognized prior to the war that the U.S. could easily out produce them. They were counting on U.S. public apathy and lack of taste for the war. After Pearl Harbor, U.S. public opinion shifted drastically. Yamamoto, who had attended Harvard and served as Naval attache in Washington told the military leaders not to start a war unless they were prepared to march down Pennsylvania Avenue and dictate surrender terms in the White House.
By 1945, Japanese public opinion had shifted and the militarists who brought disaster on their country were held in contempt and hatred by the public.
I’d even push it back to PH. Once our industrial might hit stride it was over for Japan. They were simply out built and out fought.