What if Japan attacked the Dutch East Indies in 1936?

What if Japan had attacked the Dutch East Indies in 1936, based on lobbying from the Navy to gain the valuable archipelago located at the strategic maritime crossroads of the Indian and Pacific Oceans, offering Japan a position outflanking Singapore and Manila Bay, and providing already extensively developed fuel resources to fuel Japan's Navy, Army, and economy under Japanese, rather than foreign control, and coincidentally, offering Naval Admiral, Captains and other officers a chance for glory and promotion?

Considered as a one-on-one struggle, as of 1936, Japan should be completely conflict in its ability to win a near term victory over the Dutch in the East Indies, conquer the territory, and hold it against a Dutch counter-attack, given the distance any Dutch relief force would have to travel.

The archipelago's distance from Japan's land-based airbases would be a serious operational and logistic problem to overcome, and least for the most valuable, populous, and productive western and central islands of the East Indies, although IJN carriers could project limit airpower against most parts of the islands from the beginning. Engaging against enemy land-based air power in the defense with only carrier-based air would be risky and hazardous however.

An operational solution could be found, without stepping on the territory of other powers, like Britain, the USA, or France, by rapid successive sequential operations starting in the easternmost of the Dutch East Indies, where land-based Japanese aircraft (likely naval rather than army, but still land-based) could provide powerful support from bases in the Japanese Micronesian Mandated islands to back up combined Special Naval Landing Forces supported also by carrier-based aircraft and battleship bombardment, to rapidly capture Dutch airfields for Japanese use.

The Japanese, bringing along engineering troops, could follow up each successive island group seizure with rapid repairs of Dutch airfields, forward transport of land-based air, and attack on the next Dutch-owned objectives, in support of the Combined Fleet and landing forces.

A rapid pace of maneuver would be essential to keep defeating the Dutch in detail and prevent defensive consolidation, and reduce time for other powers to consider possible intervention in the bilateral conflict.

Once all the principal islands were secured and the major Dutch forces in the region defeated, their continued occupation would be a fait accompli, and peace treaty and war termination with Netherlands would be a diplomatic formality in all likelihood. The Netherlands, despite being an economic and financial power, were not a vast manufacturing, military, nor territorial power, nor highly populous and thus in a position to undertake a long-distance reconquest of the East Indies.

After establishing occupation, Japan could repair damaged facilities, reorient the oil and food exports to the Japanese imperial market, and theoretically emerge stronger and self-sufficient, having a naval/maritime complement to the Army's Manchukuo project.

Well, that's sounds great, so why didn't Japan do it? What could go wrong?

Wasn't Japan bogged down in a war with China in 1936?

As it turns out, if it was a war, it was not a very hot one at this time. Japan enjoyed control over the Manchukuo and Inner Mongolian (Mengjiang) puppet states north of the Great Wall of China, and had compelled China to keep large parts of Beijing's province of Hopei demilitarized under the He-Umezu truce agreement. For most of 1936 until the Xi'an incident of December, Chiang remained preoccupied with preparing an encirclement and annihilation campaign against the Communists who had survived the Long March in Shaanxi province and ignored calls to push back against Japan. Chiang did not start pushing back against Japan until July 1937, and the Japanese were not getting political signals he might be heading in that direction, until after he paused anti-Communist operations during/after the December 1936 Xi'an incident and increased resistance and unity talk.

What about intervention of other powers, like the USA or Britain, the Philippines, Malaya and Borneo are in between the Dutch East Indies and Japan you know?

The Japanese could quite plausibly calculate by this time, middle or late 1936, that none of these powers would intervene directly or effectively in a Dutch East Indies war, no matter what they said. Such a calculation could quite plausibly be correct. It would give us a pair of equally interesting scenarios if the Japanese calculation turned out to be correct, OR, if it turned out to be incorrect, and another power intervened in the war.

Why should Japan have confidence in non-intervention by outsiders? 1) Outside powers and the League of Nations had not militarily intervened, nor economically sanctioned Japan over the Manchurian invasion of 1931-33, and the adjunct short-term Shanghai invasion, despite diplomatic condemnation. 2) More recently outside powers had not intervened militarily, or sanctioned effectively or persistently, against Italy's invasion of Abyssinia, and ultimately its annexation from 1935-to April 1936, despite condemning it. They tried some sanctions but did not persist. Relevant to Japan's situation, Abyssinia was adjacent to British and French colonies, but still they permitted Italy to expand next to them and to use Suez. This might be explained away by economic or racial factors. Cynically, Abyssinia was poor and hardly exported anything, so maybe it wasn't worth a struggle to London and Paris, but the East Indies produced valuable petroleum and hardwood and limited rubber, rice and coffee exports of greater commercial value. Or perhaps white leaders in London, Paris, Washington could tolerate white Italians conquering black Africans, but not tolerate Asians ousting white Dutch rulers to take control over a large Asian people and Asian land. But other events of the 1930s suggested that weak will in the west and aversion to conflict was about a more general preference than just racial bias: 3) In 1934 (or 1935?) Britain had signed the Anglo-German Naval Treaty, showing a lack of determination to hold its full degree of naval superiority over Germany, even in the North Sea close to home, and 4) In 1936, France (and Britain) failed to resist the German remilitarization of the Rhineland, right upon her border, closer than the metropolitan Netherlands is to France, making any concept of Paris or London extending deterrence out to a distant Dutch *colony* less credible and more of a stretch. 5) All West European powers showed preoccupation from July 1936 onward, with the Spanish Civil War, which was turning out to be a protracted struggle, not a quick coup d'etat. Germany and Italy were intervening directly in support of the Spanish Nationalist rebels. The British were pulling the French into the unsuccessful Non-Intervention Committee and policy, to try to contain the conflict, and not actively countering Italo-German influence or encouraging France to do so (in fact discouraging it). As another bonus from a Japanese point of view, the Spanish Civil War was drawing heavy attention from the Soviet Union and allied ideological movements, leading to deployment of Soviet advisors, weapons and international volunteers, which diverted Soviet attention from northeast Asia and the Manchukuo-Korea frontier.

This accounts well for the alternate preoccupations and likely hesitations of European powers to intervene in the Indies. What about the USA? From a Japanese vantage point, the Roosevelt Administration's first term had been almost exclusively focused on domestic policy, not passing anything like a two-ocean Navy bill, with any naval construction advertised more as a jobs program than a security program. FDR was preoccupied with his reelection. If anything, his foreign policy as shown in the Americas, was one of retrenchment from intervention in neighbors' political affairs. With respect to the Far East, the Americans formally set a timetable for the independence of the Philippines in 1945, through the Tydings-McDuffie Act of 1935. Despite some posturing of the US Navy at the tail end of the Hoover Administration during the Shanghai affair, and the failure of any Naval talks in the mid-30s, the relative quiet that had settled on the China-Manchuria front since 1933 had not added any particularly urgent stressors to US-Japanese relations by 1936. America was somewhat economically recovered from its depths of 1933, but hardly looking outward, except for trade opportunities, which it sought with Japan as much as with China and European colonies like the DEI.
And in case, should any of these powers, America, Britain, France, the USSR, turn against Japan in the medium term or long-term, the Dutch East Indies would be a great strategic asset for Japan to possess from the beginning of any serious conflict escalation, rather than not to have.

Didn't the Japanese Army, not Navy, run everything in 1930s Japan?

It's more complicated than that. Army officers and societies organized and roamed free making up their own foreign policy as they went along (like the Manchuria incident of 1931, and earlier and later incidents), assassinating politicians and generals they felt insufficiently supportive, and attempting coups d'etat, from the 1928-1936 timeframe. But so did some Navy officer groups and societies. In February 1936 a spiritualist Army faction attempted a coup and made some headway, but was suppressed by an angry court, Army senior command, and Naval forces. The plotters, unlike in previous cases were sternly dealt with, being either executed or forced to commit suicide. The result was sort of a compromise, since the Army coup was stopped, but only with the help of other parts of the Army, with ideas not 100% dissimilar from the plotters. Initiative coups and assassinations of politicians and generals pretty much ceased at this point from military personnel. But people always worried they could happen if top leaders adopted policy broadly unpopular with the Army or Navy. The Army and Navy generally had different priorities, but both got increased funding and their share of personnel and equipment budgets, and policy influence, in the spoils system.

When considering Japanese military factions and their different priorities, and the Japanese Navy and Army and their different priorities and positions, it is important to remember that differences =/= diametrical opposition and differences =/=mutual hatred. Neither service was a monolith, and both Army and Navy contained "Go North" and "Go South" advocates and it is easy to provide quotes from both.

Edward Drea, writing on this era has noted that one of Emperor Hirohito's recurring critiques and lines of questioning toward the Army regarding its course of action in Manchuria and China was whether Japan was overreaching and investing in an unbalanced commitment to the Army in the mainland, and not taking enough care to keep Japan's Navy and Air forces and maritime position adequately strong to deal with possible threats to Japan's interests from the USA or Britain.

So, I could imagine it being plausible that a strong, enterprising Navy-centric group, joined by some Army officers and Civilian officials with similar ideas and economic justifications, could build a powerful case for domination of the Dutch East Indies in the mid-1930s.