It’s always been my impression that Japan’s conquest of Manchuria was a marginally positive move, more than negated by its further incursions into China. But reading this short, but dense, piece by James Graham over at HistoryOrb, I’m inclined to refine that view a bit:

Prior to the China Incident Japan had some success in achieving its economic aims in Manchuria. By 1931 Japan had spent 1.5 billion yen in Manchuria an amount rising to 3.7 billion yen by 1936. This was more than the total Japanese budget for any one year. Japan was able to invest in railroads, highways, hydro-electric plants and improve the area’s harbours and navigable rivers. Useful amounts of iron, aluminium and other minerals were also discovered. In contrast output of synthetic oil and coal production were modest at best. Both were vital industries where Japan was heavily reliant on foreign sources of supply. The failure of Manchuria to replace these sources was thus a huge disappointment. Five hundred thousand Japanese immigrated to Manchuria between 1931 and 1945 with half of these being the agricultural settlers Japan had aimed to resettle. The reality however was that few Japanese could compete with the locals who were prepared to work for much lower wages. Most lasted only six months before joining their countrymen as supervisors, police, bureaucrats, soldiers and foremen in Manchuria and later China itself. Despite these setbacks the occupation of Manchuria was initially seen by Japan as relatively inexpensive and successful.

One is left to wonder (and always well, as it is with such things) if Japan would have been so driven to further Chinese adventurism, were it not for the global tide of protectionism – policies brought about in response to depression which only made matters worse.