In World War 2, the bombing of Pearl Harbor by the Japanese drew the U.S. into the war.
December 7th, 1941. The surprise attack on Pearl Harbor by Japan.
Germany's invasion of Belgium, the sinking of the Lusitania, and the Zimmermann note drew the U.S. into World War 1.
The US Civil War.
after World War 1ANS 2 -Women in the US finally got to vote after the Nineteenth Amendment was passed in 1920.
World War I
The treacherous Japanese attack on Pearl Harbor on December 7th, 1941 drew the US into the war.
The Japanese bombing of Pearl Harbor.
Bombinmg pearl harbor
The War of 1812, western expansion, and finally the sinking of the Lusitania dragging America into it's first world war.
World War II
Japan bombing Pearl Harbor
The unprovoked attack on Pearl Harbour by the Japanese
December 7th, 1941. The surprise attack on Pearl Harbor by Japan.
Germany's invasion of Belgium, the sinking of the Lusitania, and the Zimmermann note drew the U.S. into World War 1.
The category pretty much answers the question, US dropped two A-bombs and Japan believed that they US had more. We didn't.
Japan
The attack on Pearl Harbour, by the Japanese, directly brought the USA into the second World War. America declared war on Japan, and then Germany declared war on the USA, some days later.