October 7, 1928, after a period of reorganization, the Australasia Army advanced eastward from Oregon, with their spearhead aimed directly at Idaho.
Geographically, the position of Idaho was still very important.
Although it wasn't a coastal urban city with a highly developed population, Idaho's west belonged to Washington and Oregon, which were part of the coastline; to the east were the agriculturally and pastorally advanced states of Montana and Wyoming; and to the south were Nevada and Utah, making it a relatively central and pivotal area in the western United States.
If Idaho were lost, Montana and Wyoming would be like fish on a chopping board, left at the mercy of the Australasia Army.
What's more, just to the east were North and South Dakota, and past Minnesota lay the Great Lakes region.