The USN was weaker and the Japanese could have sunk all the US carriers??? The US was roughly equal in terms of the large "fleet": carriers: The US had the Lexington, Saratoga, Yorktown, Enterprise and the recently commissioned Wasp & Hornet, as opposed to the Japanese Akagi, Kaga, Soryu, Hiryu, and the recently commissioned Shokaku & Zuikaku. So, if you say the Japanese could have sunk all US carriers, you also have to accept the fact that the US could also sink all the Japanese carriers. You also have to face the fact that the Americans also believed that they could defeat the Japanese rather easily, just as the Japanese though that the Allies would fall to defeat just as easily. Although the US high command was practically begging FDR not to provoke the Japanese because they knew that the US needed about 6 months to complete their military buildup in the Pacific - which was already falling behind schedule. Germany was the bigger threat, that is true, however the US was not really in a position to effect any diplomatic or military outcome with Germany. Any economic "wars" were essentially meaningless, and any military action would need a declaration of war - which the US population was not wholly ready for, nor was the US Army ready to fight a war in Europe due to a lack of...well, everything. Also, while Germany was the larger threat, Japan was the "easier" target, and it was believed that Japan would cave to American demands rather than risk a war that Japan could not hope to win, and would likely result in her national destruction. EDIT: have your actually read the Japanese proposals & counter-proposals...They are a joke, and poor ones at that.