As tensions rose during the late 1930’s in both Europe and Asia, the Canadian defence assessment of military threats shifted from the Pacific to Europe. Canada’s West Coast had received a larger share of attention as shore emplacements were upgraded, defence plans were updated, and general military preparations were undertaken. As Japan expanded it’s military operations throughout Northern China and then into the coastal areas further south, Britain, the US and began to recognize that Japanese Naval, land and air power had become an aggressive, expansionistic threat to not just Asian targets but to the American West Coast.
Shore battery emplacements in Vancouver, at Point Gray and Stanley Park, Victoria, --------, Prince Rupert and along Johnstone Straight were activated and drilled. The U.S. was engaged in upgrading their coastal defences along the Straits of Juan de Fuca and other strategic areas along the Oregon and California coast. The US military establishment was concerned that Canada was not doing it’s part in preparing for a potential Japanese attack and that they would have to intervene to protect Canada if Japan threatened a landing.
The Canadian government was worried that their sovereignty might be ignored if the U.S. decided to initiate operations in Canadian waters under the guise of protecting Canada. This concern did not disappear but did diminish in September of 1939 when all focus shifted to Europe as war exploded across the continent with the German invasion of Poland, the initiation of operations by U-boats against allied shipping and naval vessels. The west coast priority became the Atlantic priority and Halifax became the centre of the Canadian naval build up. This did not however slow down Japanese operations in South East Asia and Japanese preparations for war which ultimately lead to Pearl Harbour on December 7th of 1941.