Here's what President Roosevelt said to his Cabinet after the attack on Pearl Harbor

AP

Three U.S. battleships are hit from the air during the Japanese attack on Pearl Harbor on Dec. 7, 1941.

Seventy-five years ago, to the day, President Franklin D. Roosevelt ushered his Cabinet into his study for what he deemed the "most important" Cabinet meeting since the onset of the Civil War in 1861.

Pearl Harbor, a naval base in Hawaii, had just been attacked by the Japanese, hastening the US entrance into World War II.

Michael Beschloss, a presidential historian, tweeted a readout of the fateful meeting, on Wednesday - the 75th anniversary of the attack. 

Roosevelt told the assembled Cabinet members that the Japanese had to have been planning the attack for weeks, while, at the same time, envoys had asked for a meeting with Secretary of State Cordell Hull to begin peace negotiations.

The president also asserted that the Japanese had been working in consort with the Nazi regime, who believed that victory was imminent.

The Cabinet members, including Roosevelt and Hull, resolved to ask Congress to declare a state of war. Hull called it the "most important war in 500 years," and Secretary of War Stimsom asserted that the Germans had "inspired and planned the whole affair."

The rest, as they say, is history. 

Here's the full readout from the meeting: