What event was triggered by the attack on Pearl Harbor?

The attack on Pearl Harbor on December 7, 1941, was a pivotal moment in modern history that directly led to the United States’ entry into World War II. This surprise military strike by the Japanese Imperial Navy against the U.S. naval base in Hawaii resulted in significant damage to the Pacific Fleet and the loss of over 2,400 American lives. The attack galvanized public opinion in the United States, which had largely been isolationist prior to this event.

In the immediate aftermath, President Franklin D. Roosevelt delivered a speech to Congress, famously calling December 7th "a date which will live in infamy." This speech led to Congress declaring war on Japan the following day, marking a decisive shift from a stance of neutrality to active involvement in the global conflict of World War II. The attack on Pearl Harbor not only brought the United States into the war but also changed its foreign policy approach permanently, as it engaged with other Allied nations against the Axis powers.

It’s important to note that the other options do not accurately reflect the consequences of the Pearl Harbor attack. World War I had concluded over two decades prior, the formation of the United Nations occurred after the end of World War II in 1945, and while U.S