On December 7, 1941, the Imperial Japanese Navy launched a surprise attack on the U.S. naval base at Pearl Harbor, Hawaii. The attack resulted in the deaths of over 2,400 Americans and significant damage to the U.S. Pacific Fleet. In response, the United States declared war on Japan the following day.
2. Germany's Declaration of War:
Following the attack on Pearl Harbor, Nazi Germany declared war on the United States on December 11, 1941. This was a direct result of the Tripartite Pact, a military alliance between Germany, Italy, and Japan, which stipulated that an attack on one member would be considered an attack on all.
3. Unrestricted Submarine Warfare:
Prior to the United States' entry into the war, Germany had been conducting unrestricted submarine warfare against Allied shipping in the Atlantic Ocean. This meant that German U-boats were sinking merchant ships without warning, resulting in the loss of lives and disruption of vital supply lines. The United States had repeatedly warned Germany to cease this practice, but it continued, prompting the U.S. to take action.
4. The Lend-Lease Act:
The Lend-Lease Act, passed by the U.S. Congress in March 1941, allowed the United States to provide military aid to Allied nations without requiring immediate payment. This aid was crucial in supporting the war efforts of Britain, France, and other Allied countries against Germany and its allies.
5. The Atlantic Charter:
In August 1941, U.S. President Franklin D. Roosevelt and British Prime Minister Winston Churchill issued the Atlantic Charter, which outlined their shared vision for a postwar world based on democracy, freedom, and collective security. The charter further strengthened the alliance between the United States and Britain and paved the way for their joint involvement in the war.
6. Public Opinion:
Public opinion in the United States shifted dramatically in favor of joining the war following the attack on Pearl Harbor. Prior to the attack, many Americans were isolationist, opposed to direct involvement in foreign conflicts. However, the surprise attack and the subsequent declaration of war by Germany galvanized public support for entering the war and defending democracy against the Axis powers.