US engagement in WW2 was in response to an attack just before a declaration
of war by Japan and another attack just after a declaration of war by
Germany.


1)If you read some history,you must know that FDR was very eager for US
engagement.
2)If you read history you must also know that that FDR promised the nation not
enter war unless attacked (a requirement of domestic politics)

A solution to satisfy two contradictionary requirements=The Pearl Harbor trap

Pearl Harbor was only one of US (Union) vaccination operations.
Short history of US (Union) is full of such operations ,like
Ft.Sumter,Maine,Pearl Harbor,9/11 you name it.

If Hitler'd won the war , Nazi version of Reichstag fire would be the official
version.period.

Reading history from the books is by no means enough,one must learn to "read"
events themselves.