The correct answer to this open question is the following.
Although there are no options attached we can say the following.
I think that the United States indeed had a moral obligation to enter WWII before the attack on Pearl Harbor because their historic allies were part of the confrontation against a common enemy: the Germany of Adolph Hitler.
The United States had been supporting Great Britain and France since World War I.
First, the US loaned money, sent war supplies, and finally, the US had to enter World War I after the sinking of the Lusitania ship and the interception of the Zimmerman telegram.
So in World War II, their allies were again being part of the confrontation and the threat was equal to the United States. If Germany had captured Great Britain, this represented a major risk for the United States and its political and economic interests.
Furthermore, some historians think that the attack of Pearl Harbor was justified from the perspective of the Japanese Army according to the circumstances of that moment during World War II.
The Japanese wanted retribution for the recent oil embargo decision of the United States. In August 1941, the US federal government imposed an oil embargo as a punishment for the Japanese invasion and presence over different regions of Asia.
