In July 1941, Japan moved to occupy the Southern half of French Indochina to sever supplies for the Chinese government, which induced a crippling oil embargo.
While this might have induced the reaction McCollum had hoped for, the Japanese government demanded they be permitted to exert control over their occupied Chinese territories, something the United States was unwilling to accept.
We must be ready on both sides and probably strong enough to care for both.This statement implies that, while the United States may have desired support to Britain, it did not warrant a reckless provocation might have impeded, in his analysis, the prosecution of a war with Germany.
The characterization of the McCollum memorandum as a recipe for war was not accepted by U. S. Army military historian[4] Conrad Crane, who wrote: A close reading shows that its recommendations were supposed to deter and contain Japan, while better preparing the United States for a future conflict in the Pacific.
There is an offhand remark that an overt Japanese act of war would make it easier to garner public support for actions against Japan, but the document's intent was not to ensure that event happened.