On September 2, 1874 former President of the Confederacy, Jefferson Davis, delivered a speech in Memphis, Tennessee denouncing a massacre of sixteen black men a week prior in Trenton, TN.
To say for any reason that the United States should not have entered the Second World War is ludicrous. We were presented with the very real threat of anti-Semitic fascism taking control of Europe and the world. We had to enter, to save the vote of the people and of society.
The US had no choice but to enter WWII when it did. Once the Japanese attacked Pearl Harbor, there was no way that the US could stand by and allow that to happen without a response. In hindsight, the US should probably have gotten involved against Germany earlier. We know now that the Nazis were a totally evil regime.