Answer:

The United States could have avoided becoming involved in WWII by continuing its policy of isolationism and remaining neutral in the war. However, Japan's surprise attack on Pearl Harbor on December 7, 1941, resulted in significant loss of life and damage to the American Pacific Fleet, which prompted the United States to declare war on Japan the next day.

Whether or not the decision to retaliate against Japan was worth the cost of American lives is a subjective question that can be debated. However, it is generally believed that the attack on Pearl Harbor galvanized American public opinion in favor of entering the war, and that without American involvement, the war in Europe and Asia might have had a very different outcome.

If the United States had chosen to stay out of the War and continued to focus on domestic issues, it is likely that the outcome of the war would have been different. Without the significant resources and manpower that the United States provided to the Allied powers, it is possible that the Axis powers would have been able to achieve their territorial and ideological goals. Additionally, US economy would not have the stimulus from being a war-time economy, which might have slowed down the recovery from the great depression.