December 7, 1941 is studied as one of the most brilliantly executed surprise attacks ever conceived, yet its own planners came to see it as a catastrophic strategic mistake. This episode traces the decades of resource rivalry behind it, including a 1934 memo describing how Standard Oil’s Walter Teagle secured regulatory loopholes that made America the main fuel supplier to the Japanese war machine. When the oil embargo and the Hull note demanded withdrawal from China and Indochina, Japan’s leaders, disciples of Alfred Thayer Mahan’s decisive battle doctrine, gambled that sinking American battleships would buy six months to a year and break American morale.

We examine the missed signals: Billy Mitchell’s 1924 warning, Dick Ellis’s claimed British intelligence tip, the 14-part message that severed relations but never declared war, and the radar blip dismissed as incoming B-17s. Nagumo’s 353 aircraft killed 2,403 Americans and sank or damaged eight battleships, but left the carriers, oil tanks, repair yards and submarine docks untouched. The episode explains why 1941 doctrine made his withdrawal logical, why Yamamoto later called it a great mistake, how Hitler’s needless declaration of war solved Roosevelt’s isolationist problem, and how the Niihau incident fuelled internment on the mainland while Hawaii’s economy made mass internment impossible.

• How American oil and the Hull note backed Japan into a corner of its own making
• Why the 14-part message was not a declaration of war and how bureaucratic delay made it late anyway
• The case for and against a third wave, from night landings to unknown carrier positions
• The Niihau incident and the stark contrast in internment between the West Coast and Hawaii
• Plan Orange, Plan Dog, and Admiral Hara’s verdict that Japan won a great victory and thereby lost the war