Why Did The US Enter WW2?
Quick & Short Answer:
1. First Reason: The Sudden Japanese Air Attack At Pearl Harbor, Hawaii Island. The Sudden Airstrike Killed 2,390 American Service Members And Civilians. 2. Second Reason: Nazi Germany And Fascist Italy Declared War On The United States of America. This Directly Led To The United States Involvement In The Conflicts of Europe. 3. Third Reason: The United Kingdom Was The Most Reliable Ally of The United States. The US Had To Enter The War To Save And Help The United Kingdom & Other Allies. 4. Fourth Reason: The United States of America Was The Protector of Democratic Values. It Was Important To Stop The Expansion of Fascist Ideologies By Protecting Democracy And Human Rights. Follow The Article & Watch This Embedded YouTube Video To Understand Better. |
The United States of America first thought that the War was Europe and Asia’s internal armed conflict and they had nothing to do with it.
On the other hand, due to their neutrality, they were able in supplying their goods to various countries, including Axis and the Allied.
It helped them in making a lot of money.
But suddenly what happened that they broke the neutrality and entered into the greatest destruction in human history.
Let’s try to clear doubts throughout this post, step by step.

4 Main Reasons Why The US Entered World War 2
1. The Sudden Japanese Attack On Pearl Harbor
In 1941, on the month of December 7th, the Japanese airforce made an operation in America’s Pearl Harbor, located in Hawaii island.
It was an airstrike from the Japanese side on America’s main Navy base in the Pacific Ocean.
Including 21 ship damages, almost 2400 people died in that two hours sudden attack.
The incident was like a heavy stroke in America’s self-dignity and failure of intelligence.
Because just an hour before, diplomats between these two countries were talking about solving the disputes in the Pacific region.
Hence, the sudden attack almost shocked the entire United States.
After a day the incident, on 8th September 1941, United States President Franklin Delano Roosevelt declared war on Japan and made its first entry into WW2.
Experts believe that if Japan didn’t attack Pearl Harbor, then America probably would not have been involved in World War II.
Many experts also consider this incident as the main reason for the defeat of the Central powers.
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2. Nazi Germany And Fascist Italy Declared War On The USA
On 27th September 1940; Hitler’s Nazi Germany, Mussolini’s Fascist Italy, and the Empire of Japan signed a treaty in Berlin.
The treaty was the ‘Tripartite Pact’, also known as the ‘Berlin Pact’. In the history of WW2, this pact was the beginning of the central powers.
In the treaty, these three nations came to an agreement that they would protect each other militarily, in case anyone of them faces military threats from another nation.
In short, they signed the agreement to fulfill and protect each other’s expansionist ambitions.
In 1941 on 8th September, the United States of America officially declared war on the Empire of Japan.
Therefore, as per the agreement, on 11th September 1941, Nazi Germany and Fascist Italy also declared war on the United States.
On the same day, the USA also had to declare war on Germany and Italy, even though they had no big conflicts against each other.
After that, the USA directly joined allied nations and entered into the Wars in Europe and Asia.
[Interesting fact: Until the attack on Pearl Harbor, the US had been exporting its goods to Germany. Even in 1939 and 1940, their exports to Germany were 75 times greater than the years before]

3. Had To Enter Save And Help The United Kingdom
However, this was a secondary cause of America’s entry into the war; but we can also count it as a cause.
Actually, many United States experts believed that their country was incumbent over the British winning the war against Axis forces.
If Nazis were able to defeat Britain, they would also plan to invade the USA in the near future.
So, helping the Britishers would be a better choice for Americans rather than staying neutral.
Either way, the United States and the United Kingdom were both democratic nations.
From this side, the US had already some sympathy for Britain.
4. To Protect Democracy And Human Rights
This one is not a primary cause, but it also has a lot of importance.
The United States of America is a country that has fought some huge battles to protect democracy and human rights values (Life, Liberty, and the pursuit of Happiness).
In their history, two of the major battles were the Revolutionary war of independence and the Civil War.
In these great wars, millions of people gave up their lives only to protect two things; one was democracy and the other was human rights.
The United States was well aware that if the Axis power wins the World War 2, then they would entirely eat up all the democratic systems in the world.
Because Germany, Italy, and Japan were authoritarian nations.
Therefore, though, in the beginning, they didn’t involve in the conflict, but they never wanted the Axis forces’ victory here.
After the Pearl Harbour incident, they directly got a chance to fight again for democracy.
Why is Nigeria not part of the 1&2world war
Nigeria participated in WW1 & WW2 as a part of the British Empire