What if Japan invaded Australia/NZ?

for conversation sake, if the japanese took australia and new zealand by storm and succeeded in occupying the place, then what?

could the japanese perhaps use the land to their advantage? could they use whatever natural resources australia had to benefit their army? is it feasible for them to defend their territory against the US? can they launch a successful invasion on other parts of the pacific? would there be more to be lost than gained in occupying australia/new zealand?


I'd like to hear some comments.

 

I do not think that Australia would have been to Japan's benefit. Too much land, too many hard to control people, and too far away from home. Not enough resources to help their war effort.

 

But if Australia was taken it stops it from being a base for the Americans.
America used Australia to base very large Army, Air and Naval forces and had huge material facilities throughout the country for the counter attack against Japan.
The Japanese Navy wanted to invade Australia but the Army said they didn't have enough divisions for an operation that big, so Australia was spared.

Thank heavens the Army won that argument.

 

Just how much of the Japanese troops in 1942/43 would have to be there to invade Australia? 30%? 40%?

 

The Army said it would need at least 20 divisions for the operation, and when you realise that they only used 11 divisions in their blitzkrieg through the Pacific, it would have been a pretty big task.

They had about 40 plus divisions in China and Manchuria.

 

100% agree

I think even if Japan ever had what it takes to seize Australia, which I doubt (just think about the distances), the economical benefit would not be worth, neither depriving USA the strategic and logistic situation of Australia.

 

Other than I think the Japanese had absolutely no chance to actually pull this off, the major hit would be for troops in the Middle East / mediterrainian where several Australian divisions were significantly employed. Their loss would have been a major blow to the Commonwealth efforts in that theater.
As for the US in the Pacific, it would have actually helped their overall war effort.
The loss of Australia would have practically ended the SWPA war effort, eliminating MacAuthur's command there (I have no doubt he would be employed elsewhere). This would have freed up several additional US Army divisions, lots of squadrons of aircraft etc.
Once the USN started to drive across the Pacific they would still have crushed the IJN and IJA at every turn. Bases? The USN brought everything with them. They were miles ahead of anyone in having mobile forward bases.
At Ulithi Atoll in 1944 the USN had the equivalent of a full shipyard based on tenders anchored in the lagoon. This included floating drydocks (note the s) capable of lifting any ship in the US fleet. Short of very heavy battle damage ships did not return to the US for repairs.
For building the Marianas B-29 bases 3 mobile asphalt plants were used along with several floating dredges and a massive amount of mechanized construction equipment. Here is an earlier thread on this:

seebees in the pacific

 

What might have been.

In February 1942, Japanese Admiral Yamamoto, proposed an immediate invasion of Australia. He had just implemented his bombing raids on Darwin in the Northern Territory. He pleaded with the Japanese General Staff, to land two Japanese Army Divisions on the northern coastline of Australia which was very poorly defended. They were to follow the north-south railway line to Adelaide, thus dividing Australia into two fronts. Once Adelaide had been taken, a second force would land on the south east coast of Australia and drive northwards to Sydney and southwards to Melbourne.

General Yamashita agreed with Yamamoto's Invasion Plan and even volunteered to lead the invasion. However, the plan was opposed by Japanese Prime Minister, General Tojo, as he believed that there were no contingency plans considered for Yamamoto's Invasion Plan.

Emperor Hirohito decided to postpone the Invasion Plan until Japanese forces had taken Burma and joined forces with the rebel Indian Nationalists. The outcomes of the Battles of the Coral Sea and Midway ensured the Invasion Plan for Australia was never revisited.

Perhaps Yamamoto was on the right track to invade, although the Japanese might have been stretched, Australia at the time had their best divisions overseas and the Navy and Air force were pretty threadbare, the Japanese were on a roll against very limited opposition.

The best chance of an Japanese invasion of Australia would not have been through a Perth or Darwin axis. These points could be essentially neutralized by minor attacks.

The focus of invasion would have been the south-eastern boomerang. What would have happened if Japan had won the battles for Papua and the Solomon islands? In the event of a delayed response from the United States the Japanese would probably have attempted to invade Australia. This would have been only possible if they were able to withdraw troops from China and find sufficient shipping to land the troops on the east coast. A successful lodgment would have extended their supply lines further and only in the event of a rapid rout of Australian forces could the invasion have been sustained.


Or at least concentrated on taking Port Moresby, Fiji, the New Hebrides, Samoa and the Solomons to isolate Australia instead of moving Westward into Burma and the Indian ocean.

In February 1942, Franklin Roosevelt, decided to make Australia the main American base in the south-west Pacific.

By early '43 there were over a quarter of a million Americans in Australia, with two thirds of their supplies and support coming from Australian industry, plus large submarine bases at Brisbane and Fremantle.

But no matter what the Japanese tried, even if they did successfully invade or had better luck at Midway, Japan's defeat might have been delayed but it would still have occurred.

 

Here's another 'what if'.........

''What if'' Japan, as part of the Axis, didn't attack Pearl Harbour, and instead just attacked the European colonial possessions while doing their best to placitate the U.S. would America declare war?

Yamamoto feared that Japan did not have the resources to win a war with the U.S., so reluctantly advocated a surprise attack on the US Pacific Fleet at Pearl Harbor and then over run South East Asia, fortify island bases and bleed the Americans so much that they would eventually think it wasn't worth the effort.

But by making that undeclared attack on PH, it stirred up a hornets nest, and made the Americans determined they would never stop until Japan was crushed.

U.S. plans were, baring any direct attack against the Philippines or U.S. possessions, was a strictly defensive posture against Japan. The short term goal of the Japanese was to obtain the oil supplies, rubber, and and other strategic materials from the East Indian possessions of the Netherlands, Great Britain, and France. Given the isolationist temperament of the U.S. Congress at the time, is it questionable, even doubtful, that that the United States would have responded directly to the seizure of those foreign Colonial possessions?

When the Japanese moved in to French Indo China the U.S. placed the oil embargo but didn't threaten war.

 

Sorry that I´m answering a question with another question, but one has to be ready to answer the new possible situations before taking the first step.

What would FDR decide to do once he had required Japan to get out of China and instead Japan would go on with their war on a larger scale? (Stopping the oil transfer would leave the Japanese with 6 months´ of supply to the navy.) So it would be war sooner or later with the US as FDR left them already with the ultimatum with the China situation.

How many of you guys would have given an ultimatum to the Japanese in 1941 to get out of China and thought it was politically a great move?? Just wondering...



My answer is that FDR would declare war...

 

Probably would, but I don't think it was a forgone conclusion.

In late '41, 75% of Americans were against war with Germany even though American warships had been torpedoed by U boats and American sailors killed.

And 60% were against war with Japan.

And a telling point was when Churchill asked Roosevelt to station several capital ships in Singapore he was refused.

Then Churchill wanted an assurance that if Japan attacked British interests in South East Asia, that America would come to Britain's aid.

Again he was refused.

The American neutrality pact was overturned by just one vote, so it was a pretty close call.

On the Americans cutting off the oil. it was one thing to cut off oil to try and persuade the Japanese to get out of China and another to declare war on them with a country that clearly didn't want war.

 

1941

July 26 - July Threshold - FDR takes decisive action:
new Philippine command created under MacArthur

AVG in China under Chennault with 100 pilots

Japanese assets in U.S. frozen

crude oil embargo July 24; aviation gasoline added Aug. 1

proposal for neutral Indochina

---------

Sept. 4 - Japanese Cabinet's "Minimum Demands" and "Maximum Concessions"

demanded Burma road closed, no interference with Japan's occupation of China or Indochina, and re-open trade with Japan

only concession was promise of eventual withdrawal from China


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Oct. 2 - FDR rejects Konoye offer of summit meeting unless China troops withdrawn first

Oct. 8 - Hull demands Japan withdraw troops from China in advance of any diplomatic agreement

Nov. 26 - "most fateful document" was Hull's counterproposal to "B"

-must withdraw first from Indochina and China

http://history.acusd.edu/gen/WW2Timeline/Prelude23.html

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The site above does not open with my computer anymore unfortunately...hope though it´s not close altogether.

 

No rattling the sabres by the Americans.

When Molotov broke off talks with the Finns he said ominously ''we civilians can see no further, it's now the turn of the military''

That didn't leave much doubt to what would happen next.

Two very big mistakes were made in the lead up to the war with Japan.

First mistake was the Americans oil embargo on Japan before the U.S. completed their military build up, and virtually compelling Japan to either attack or give in to American demands.

The end result was the war lasted longer with more American casualties.

Second mistake, and by far the biggest, was the the Japanese attacking Pearl Harbour.

If anything was going to snap America from their anti war stance, it was the sneak attack on PH.

On the other hand the Japanese probably had some chance of not drawing the U.S. into the war if they just went for the British, Dutch possessions in South East Asia.

The majority of American, even amongst the military, had no sympathy for European colonialism.

Even if the Americans did declare war, the Japanese still had superiority in the Pacific.

 

I´m not sure if the Japanese were familiar with the term " better to be a lion for one day than a sheep forever " ( or something like that ). I mean it sounds like the Japanese offensive was more or less not going to get them a long lasting victory.