I have stumbled across odd references over the years to supposed Axis plans to invade and conquer the United States during World War II. I have never been able to locate historical confirmation of these plans. One colleague told me that Japan and Germany had agreed to divide governance of an occupied U.S. at the Mississippi River. Another acquaintance said the line of demarcation would be at the Continental Divide.
The U.S. Army's official history of WWII has little to say on Axis plans for North America other than their desire to degrade the U.S.'s ability to aid its allies in Europe or operate in the Pacific. Life magazine published theoretical invasion scenarios in 1942, probably at the behest of the U.S. Office of War Information to scare Americans into putting more elbow grease into the war effort.
Where can I find historical sources for these war plans, if they in fact existed? I sometimes wonder whether Japan and Germany may have leaked existence of notional occupation plans just to convince the U.S. national leadership to devote military forces to securing the coasts of the U.S. from attack. If this was a strategic deception, it would be interesting to know what FDR's war cabinet was willing to commit to coastal defense at the expense of front-line forces in the European and Pacific theaters. If anyone out there has suggestions on where I should look, just drop me a line.