What if Japan had never attacked Pearl Harbor? | WWII alternate history

In the end, it took 353 Imperial Japanese aircraft just one morning to convince U.S. Congress to vote on a declaration of war, something Winston Churchill had been trying to get them to do for over two years.
Whilst Japan had hoped the surprise attack would demoralize American morale, the opposite was the case.
But what if Japan had never attacked Pearl Harbor on that fateful day in December 1941? How different might the world look today? Here are two possible scenarios…