Interestingly WW-2 began in Sept 1939 when Germany invaded Poland and activated treaties with England and France.
December 7 1941 really just precipitated the US entry into WW-2 by Presidential decree and the US Congress declaration.
This doesn’t begin to address issues regarding our government knowledge of circumstances relative to the so called “sneak attack” by the Japanese. Much less the construction of the Japanese Navy using scrap US steel and oil embargoes etc etc.
WW2 started when Japan invaded Manchuria in 1931, it set all the wheels in motion.