Was Japan forced into World War 2 by external forces or was it wholly their fault?

by Adnotamentum

I've heard that it was promised to Japan that the western allies would not interfere against their invasion of China so long as no one intervened on their side. Was this the case? Were they therefore tricked into starting World War 2 when the US embargoed them?

Domini_canes

Were they therefore tricked into starting World War 2 when the US embargoed them?

No, the Japanese made a series of deliberate decisions that led to war.

I would point you to Chapter 17 of Joseph Maiolo’s Cry Havoc in which he depicts the logic of arms races and how it influenced Japanese decision making. From pg 387 and following he details the pressures that the Japanese found themselves subject to: a war in China that wouldn’t seem to end, a scarcity of resources that could be “solved” by either moving north (into Russia, especially after Barbarossa began) or south (into Indochina and the Dutch East Indies). The army favored the northern plan, while the navy favored the southern approach. Russia failed to collapse as predicted, making the northern plan less attractive. The Dutch East Indies were a great source of oil, but the Japanese concluded that the British were highly unlikely to simply accede to Japan taking that territory. As such, an assault on the British bastion in Singapore would remove a way for the oil to be interdicted—but the “old guard in top posts in the navy”also concluded that the British and Americans were “indivisible.” (Pg 388)

The critics of the old guard—bellicose staffers who in the 1930’s had backed the anti-arms control fleet faction against the treaty faction—rejected this sort of defeatist thinking. If you accepted that war against the United States was unwinnable, then you handed the army predominance in national policy making and Washington a veto over foreign policy. With the Americans set to build a gigantic two-ocean fleet and vast air armadas, and the alluring but deceptive exemplar of Hitler’s Blitzkreig in their brains, the navy’s ultra-hawkish staffers began to speak of the logic of fighting the United States in a lighting action sooner rather than later. (Pg 388)

The navy won the debate over the army (and got a much larger amount of the steel allocations for their fleet-building programs), but delayed in taking action as diplomatic attempts to gain their objectives continued. It was hoped that a settlement could be reached so that a conflict with the US could be avoided.

Admiral Kondo Nobutake of the naval staff summed up his service’s awkward problem: “The navy has not yet completed its war preparations vis-a-vis the United States. They will be completed next April and Japan will stand a fair chance of winning on the basis of ‘quick encounter, quick show-down.’ But if the United States should turn the war into a protracted struggle, it will become very difficult for Japan. On the other hand, the United States is rapidly building ships and, in the future, discrepancies in the naval ratios will widen and Japan will not be able to catch up. In this sense, today is the most advantageous moment for starting a war. (Pg 389)

Maiolo then details the diplomatic hopes of firebrands within the Japanese command.

[T]he Germans would help compel the Dutch authorities to agree to Japanese demands for more oil; Berlin would broker a pact between Moscow and Tokyo; Chaing Kai-shek would come to his senses and plead for peace terms: the Americans, always “level-Headed,” So Matsuoka said, would also see reason; if they did not, the Japanese Empire, allied with the Nazi regime and perhaps even supplied with Soviet raw materials, could face a long war against the United States anyway. (Pg 389)

None of the above happened. When Japan moved into northern Indochina (September 1940) the US cut off exports of scrap metal and aviation fuel to Japan. The English reopened the supply route to China through Burma, Chaing Kai-shek did not come to terms, and the Dutch wouldn’t budge. Neither would the Americans:

[T]he Americans wanted Japan to denounce the Axis, pull out of China and reverse the southward advance; for most Japanese officials that meant defeat. What they wanted was a truce that would allow a renewal of imports. (Pg 392)

The Japanese economy was reliant on those imports. Without imports the Japanese economy would grind to a halt.

The economy depended on trade, and because of falling earnings from exports, the war with China, and the economic embargo spearheaded by hard-liners in the re-elected Roosevelt administration, imports would soon nose-dive. In 1940 under the mobilization plan Japan’s import capacity for iron, steel, non-ferrous metals, fuel and food had been 2.6 billion yen; in 1941 it was eight million yen. (Pg 391)

In July there was another conference of Japanese commanders with the Emperor. The move into the rest of Indochina (revealed by code breakers) and fears over a Japanese attack on the Soviets or British resulted in freezing Japanese assets in the US. This “resulted in a total oil embargo on Japan” since neither the US nor the Dutch East Indies would sell oil any longer (and those two sources were the two largest contributors). (Pg 393)

Here is when we get into the direct logic for war.

From September to December 1941 the compelling language and do-or-die logic of fast-escalating arms races and total war gripped the top decision makers in Tokyo. Under the oppressive sense that time was running out, hope and fear merged into a decision reached by consensus, a decision that then flowed into fateful action. At an Imperial Conference on September 6, the emperor heard the case for plunging into all-out war against the United States, Britain and the Dutch was officially aired before the emperor. [sic] General Suzuki Teiichii, the new director of the Cabinet Planning Board, gave the most important presentation. “At this stage our national power with respect to physical resources has come to depend entirely on the productive capacity of the Empire itself…and upon vital material stockpiled thus far.” He continued, describing a situation similar to Italy’s the year before, and the sort of rationale for reckless action that had swayed even normally prudent Germans such as General Thomas to back Operation Barbarossa: “Therefore, as a result of the present overall economic blockade impose by Great Britain and the United States, our Empire’s national power is declining day by day. Our liquid fuel stockpile, which is most important, will reach bottom by July of next year…I believe it is vitally important for the survival of our Empire that we make up our minds to establish and stabilise [sic] a firm economic base.” Offered the choice between economic-military paralysis in less than a year or an admittedly risky southward thrust to seize the rich sources of oil, bauxite, nickel and rubber of Southeast Asia, the conference ratified a resolution to pursue talks with Washington and at the same time to get ready for war by mid-October. (Pg 394)

There was a final conference in November. After exhausting diplomatic approaches, Tojo reached his conclusions.

”If we enter into a protracted war, there will be difficulties,” the prime minister asserted:

The first stage of the war will not be difficult. We have some uneasiness about a protracted war. But how can we let the United States continue to do as she pleases, even though there is some uneasiness? Two years from now we will have no petroleum for military uses. Ships will stop moving. When I think about the strengthening American defenses in the Southwest Pacific, the expansion of the American fleet, the unfinished China Incident, and so on, I see no end to difficulties…I fear we would become a third-class nation after two or three years if we just sat tight (Pg 395)

In conclusion, Japan was unwilling to give up its war in China or its desire for empire. While war against the US was a risk, the potential reward of being self-sufficient in resources and having their own empire was chosen over peace.