History of the Second World War (36 page)

In July 1937, an alleged clash at the Marco Polo Bridge, another highly suspicious ‘incident’, led to the Japanese Kwantung Army invading North China proper. The invasion continued and extended during the next two years, but the Japanese became increasingly bogged down in the struggle against the Chinese nationalist forces under Chiang Kai-Shek, while in their attack at Shanghai in the summer of 1937 they suffered a repulse. This, however, turned out to their advantage in the long run, as it spurred them to correct tactical faults and tendencies to overconfidence dating back to the Russo-Japanese War — although not before they had suffered a further lesson, at the hands of the Soviet Army, in a clash over the disputed frontier of West Manchuria. Here, in the Nomonhan region, a Japanese force of some 15,000 men was encircled, and over 11,000 were lost, when the Russians brought up five mechanised brigades with three infantry divisions, in August 1939.

In that same month the unexpected news of the Nazi-Soviet Pact caused a revulsion, and the return of moderate Japanese Governments. But that reaction only continued until Hitler’s conquest of Western Europe in 1940, and in July 1940 a pro-Axis Government under Prince Konoye was put into power by the Army. Japanese expansion in China was then accelerated, while at the end of September Japan signed the ‘Tripartite Pact’ with Germany and Italy, by which these three undertook to oppose any fresh country that joined the Allies — a pact aimed primarily against intervention by America.

In April 1941 the Japanese further re-insured themselves by a neutrality pact with Soviet Russia. That promised to release Japanese forces for southerly expansionist operations — although even then suspicion of Russia and her designs led the Japanese to allot only eleven divisions for such operations, while thirteen were kept in Manchuria, and twenty-two in China.

On July 24 the Japanese, with the reluctant compliance of the Vichy Government, took over French Indo-China. Two days later President Roosevelt ‘froze’ all Japanese assets, an action that was quickly followed by the British and Dutch Governments. Thus trade with Japan was brought to a stop, particularly in oil.

Japan imported 88 per cent of her peacetime oil consumption. At the time of the embargo she held stocks sufficient for three years of normal use, or half that period at full war consumption. Moreover, a Japanese War Office survey had shown that stocks would be exhausted before the three years that were reckoned as necessary to finish the war in China, so a victory there seemed all the more important. The only available resource left lay in the oilfields of the Dutch East Indies, and it was reckoned that although the Dutch were likely to destroy their installations there before capture these could be repaired and brought into use before home stocks were too badly depleted. Oil from Java and Sumatra would save the situation, and enable China’s conquest to be completed.

Conquest of the region, including Malaya, would also bring possession of four-fifths of the world’s rubber output, and two-thirds of its tin output. That would not only be a very valuable gain for Japan, but hit her opponents worse than the loss of the oil.

These were the main factors that Japan’s leaders had to consider when faced with the trade embargo. Unless America could be induced to lift it, they were faced with a choice between abandoning their ambitions — in which case an Army coup at home might follow — or seizing the oil and fighting the white powers. It was a stark alternative. If they continued the campaign in China, but withdrew from Indo-China and stopped southward expansion, they might obtain some mitigation of the embargo, but Japan herself would be becoming weaker — and less able to withstand any further demands by the United States.

Natural hesitation to make an all-or-nothing choice may explain the puzzle why the Japanese were so tardy in striking, and deferred a decision for four months. There was also the natural instinct of military chiefs to desire ample time for completing preparations, and prolonged arguments over the strategy to be adopted. One school of thought even optimistically hoped, and argued, that America might continue to stand aside if Japan confined herself to seizing Dutch and British territory.

On August 6 Japan besought the United States to lift the embargo. That same month came the American decision to hold the whole of the Philippine Islands in the event of war, and the Japanese request for the cessation of the flow of American reinforcements thither. It met a firm reply, warning the Japanese against further aggression.

After two more months of internal argument, Prince Konoye’s Government was replaced by one under General Hideki Tojo — an event that was probably decisive. Even so, there was further prolonged discussion, and the decision for war was not taken until November 25. One precipitating factor was a report showing oil stocks as having shrunk by a quarter of their total between April and September.

Even then, the Commander-in-Chief of the Japanese Combined Fleet, Admiral Yamamoto, was given orders the same day that the attack on Pearl Harbor was to be cancelled if by any chance the continued negotiations in Washington were successful.

The naval strengths in the Pacific in December 1941 are summarised in the following table:*

*
Figures from Roskill:
The War at Sea,
vol. I, p. 560.

The main point to note is that while the two sides were closely balanced in most respects, the Japanese had a great advantage in aircraft-carriers, the crucial arm. Moreover, what such a table cannot show are qualitative differences. The Japanese force was compact and well-trained, especially in night-fighting; it did not suffer command or language difficulties as on the Allied side. There were 6,000 miles of ocean between the two main bases of the Allies, Pearl Harbor and Singapore. Materially, the Japanese Navy was much better. It had many newer ships, while most of them were somewhat better-armed and faster. Of the capital ships, only H.M.S.
Prince of Wales
was a match in these respects for the better Japanese battleships.

In Army strength, the Japanese employed only eleven divisions, out of their overall total of fifty-one, for their operations in the South-west Pacific. That was under a quarter of a million fighting troops, and with administrative troops probably a total of about 400,000. Allied numbers are more uncertain. In deciding to attack, the Japanese estimated the British as having 11,000 in Hong Kong, 88,000 in Malaya, and 35,000 in Burma — a total of 134,000; the Americans as having 31,000 of their men in the Philippines, with about 110,000 Philippine troops; the Dutch as having 25,000 regulars and 40,000 militia. Superficially, to launch a far-reaching offensive with such small odds might seem a daring gamble. In reality, it was a well-calculated gamble, as sea and air control would usually give the Japanese local superiority of numbers, while this would be multiplied by experience and superior quality of training — particularly in amphibious landings, jungle warfare, and night attacks.

In air strength the Japanese employed only 700 out of their total of 1,500 first-line Army aircraft, but these were reinforced by 480 Naval aircraft, of the 11th Air Fleet, based on Formosa — as well as 360 allocated for the Pearl Harbor stroke. Originally, the fleet carriers were allotted, and needed, to provide air cover for the southern operations. But in November, barely four weeks before the war, the range of the Zero fighters — which outclassed the Allied fighters available — was increased, so that they could fly the 450 miles from Formosa to the Philippines, and back. Thus the carriers were freed for the Pearl Harbor stroke.

Opposed to these powerful Japanese air forces were 307 American operational aircraft in the Philippines, including thirty-five long-range B.17 bombers, but otherwise inferior in quality; 158 first-line British aircraft in Malaya, mostly of obsolete types; and 144 Dutch in their territories. In Burma, the British then had only thirty-seven fighters. The Japanese superiority in quantity was multiplied by superiority in quality — particularly that of the Zero fighters.

The Japanese also owed much to their development of amphibious warfare, for such an oceanic area of islands and gulfs. Their one serious weakness was the relatively small size of their merchant marine — little more than 6 million tons of shipping — but that did not become a decisive handicap until later in the war.

In sum, the Japanese started the war with a great all-round advantage, especially in quality. In the opening stage, their only real danger lay in the possibility of a prompt intervention by the American Pacific Fleet — but that danger they forestalled by their Pearl Harbor stroke.

Intelligence is a further factor, of which sufficient account is rarely taken in setting out the balance of strength. In general, the Japanese were good in this way, owing to long and careful study of the areas beforehand — but the Allies enjoyed one immense advantage in that the Americans had broken the Japanese diplomatic code in the summer of 1940 (an achievement due to Colonel William F. Friedman). From then on, all Japanese Foreign Office or Command secret messages could be read by the Americans, and during the pre-war negotiations they knew the latest Tokyo proposals before they were presented. Only the exact date, and operational points of attack, were not passed to the Japanese ambassador.

Although the Americans were taken by surprise at Pearl Harbor, their knowledge of the Japanese codes was inherently a great basic advantage, and became such as they learnt to use it better.

Japanese strategy was geared to the dual aim, defensive and offensive, of securing the required oil supplies that would enable her to overcome a China that would in the same sweeping process be shut off from the supplies needed to maintain resistance. In taking the risk of challenging America, a power whose potential was vastly greater than their own, the Japanese leaders drew encouragement from the turn of events in Europe, where the Axis now dominated almost the whole Continent, and Soviet Russia was so hard pressed by Hitler’s onslaught that she could hardly intervene in the Far East. If the Japanese fulfilled their dream of establishing a concentric defensive ring from the Aleutian Islands in the north round to Burma in the south, they hoped that the United States, after vain efforts to break through the ring, would eventually come to accept Japan’s conquests and the establishment of what she called ‘The Greater East Asia Co-Prosperity Sphere’.

The plan had a basic likeness to Hitler’s concept of establishing offensively a defensive barrier from Archangel to Astrakhan, to shut out and keep out the Asiatic border.

Originally, the Japanese plan had been to seize the Philippines, then await the American recovery-move — which was expected to come through the mandated island territories — while concentrating her own forces to repel it. (Under the three-stage war-plan, the Japanese reckoned to complete the capture of the Philippines in fifty days, that of Malaysia in 100 days, and all the Dutch East Indies after 150 days.) But in August 1939, Admiral Yamamoto, an ardent believer in the value of aircraft-carriers, was appointed to command the Japanese Combined Fleet. He shrewdly saw the necessity of an immediate, and surprise, stroke to paralyse the United States Pacific Fleet — which he termed ‘a dagger pointed at the throat of Japan’ — and delay its countermoves. The Japanese Naval Staff rather dubiously and reluctantly accepted his argument.

The opening attack-problem was complicated by the timetable — and the zone differences (Sunday, December 7 in Hawaii would be Monday, December 8 in Malaya). But it was arranged that all the main operations would begin between 1715 hours and 1900 hours Greenwich Mean Time, and all assaults would take place in the early morning by local time.

On the American side, it had long been considered politically deplorable to abandon the Philippines, but the military argument that it was impossible to defend these islands, 5,000 miles from Pearl Harbor in Hawaii, had prevailed, so that the plan was only to maintain a foothold — on the fortified Bataan peninsula in Luzon, near the capital Manila. In August 1941, however, the plan was changed and the decision taken to hold all the Philippines.

One factor in the change was the pressure of General Douglas MacArthur, who had been military adviser to the Philippine Government since 1935, and then at the end of July 1941 had been recalled to active duty in the United States Army and appointed Commanding General in the Far East; President Roosevelt’s high opinion of MacArthur’s judgement had earlier been shown by the way he had himself in 1934 extended MacArthur’s four-year tenure as Chief of Staff of the United States Army by a year. Another factor was that President Roosevelt had come to feel that since Germany had become entangled in Russia he could venture to take a firmer line with Japan — as he had done in imposing the oil embargo. The third factor was the optimism aroused by the advent of the long-range B.17 bombers — which, it was hoped, would effectively hit not only Formosa but Japan herself She, however, struck before any large number of B.17s reinforced the air force in the Philippines. Moreover, what was not seriously considered by the American Chiefs of Staff was a Japanese stroke at Pearl Harbor.