But not 200,000 man transports, lol.
I'm trying to think of precedents for naval invasions. Nothing's really coming to mind.... but that's telling. This would have been the largest transoceanic movement of troops... in history.
The Opium Wars, for example, had only about 20,000 British troops. The entire British (non-Indian) garrison of India was only about 60,000 soldiers. Moving 200,000 soldiers across an ocean like that at those tech levels is at the minimum ultra-expensive, but might be impossible.
It depends on the conditions of transport, and the rush of the transporters. They can be delivered in several trips, like with civilian migrants. They won't arrive together, ready to fight, and it will take some time, but it can be done.
The true problems lay in the impacts for the stability of Japan and for the West of the USA's economy. It would also be somewhat expensive if they arrive in large groups, as that region should not produce enough to cater for their needs, albeit minimal.
It can be done, but it would be better done in small waves, correctly equipping and training the troops in the West Coast before sending them to battle. Otherwise they will be of very little use, and die like flies, if not outright causing mass starvation and unrest in the region.
