Imagining a Japanese Invasion of the US West Coast Post-Pearl Harbor: A Speculative Analysis

What would the US West Coast have looked like if the Japanese had invaded post-Pearl Harbor? Given the geographical, logistical, and military constraints, such an invasion was far from feasible. This speculative analysis explores the challenges and potential outcomes.

The Geographical and Logistical Challenges

The Japanese Emperor and his military leaders faced significant challenges in attempting an invasion of the US mainland. The Japanese military had no troops available to invade Hawaii during the raid itself, let alone the West Coast. Even considering the supplies and troop availability, an invasion of the US mainland was a pipe dream. The Japanese lacked the necessary naval and logistical capabilities to sustain such an operation.

Assessing Invasion Feasibility

Even if the Japanese military leaders had been willing to commit suicide over their absurd orders, the emperor himself would not have sanctioned such an operation. The logistics of such a massive invasion were beyond their reach. Even if a small force managed to land, they would have to survive on their own for weeks before reinforcement and supply could arrive.

Advanced Front-line Penetration

Analysis suggests that if an invasion had been attempted, the Japanese would likely have reached at least the Rocky Mountains. However, they would not have even made it to the West Coast due to the lack of forces to resist them. The Japanese forces would have been quickly neutralized by the US Army and Marine Corps, as well as civilians with arms.

Navy’s Role in Preventing Invasion

The US Navy and Army Air Force were capable of effectively stopping any such invasion. If these forces had been completely unaware of an invasion for a few weeks, the outcome would have been catastrophic. However, the US military would have quickly tracked and intercepted any invasion fleet, making it a “turkey shoot” for both armed forces and citizens.

Critical Mileage and Fuel Constraints

Even if the Japanese had managed to land a small army, they would have been unable to sustain it due to a lack of fuel and supplies. Any landing would have had to be made at least 300 miles off the coast, forcing the invaders to travel inland before they were spotted and neutralized. If landing near the West Coast, they would have reached about 200 miles off Catalina before running out of fuel. In the best-case scenario, they might have made it to San Francisco, where they would have faced a prolonged and deadly struggle.

Given the limited resources and the far greater military might of the US, the outcome would have been inevitable. An American military response would have been swift and effective, ensuring that any Japanese force never reached the West Coast.

The thought of a Japanese invasion of the US West Coast serves as a reminder of the strategic thinking and resources required for such an operation. The geopolitical realities of the time make it clear that the Japanese were never capable of such a feat.