The United States abandoned its position of strict neutrality during the late 1930s primarily:
1. To prevent the Axis powers from winning World War II.
As the war unfolded in Europe and Asia, the United States recognized the threat posed by the Axis powers (Germany, Italy, Japan) and their expansionist ambitions. The U.S. saw the need to support the Allies (Britain, Soviet Union, China) to prevent the Axis powers from dominating the world stage and imposing their ideologies through force.
2. To honor its commitment made through alliances after World War I.
Although the U.S. tried to stay out of the conflicts brewing in Europe and Asia, it had diplomatic and economic ties with several countries that were directly affected by the aggression of the Axis powers. These alliances, especially with Britain and France, played a role in influencing the U.S. decision to abandon strict neutrality and support the Allies.
In summary, the shift in U.S. policy from neutrality to active support for the Allies during the late 1930s was driven by the perceived threat of Axis powers' dominance and the commitment to honor alliances established after World War I.
