What if the Japanese won the Battle of Kokoda Trail?

Although the Japanese never planned to invade Australia, they did plan to isolate it from the rest of the world and perhaps, bully it into giving up the war. As part of their strategy, they landed troops on the then-Australian territory of Papua and attempted to capture Port Moresby by going through the Kokoda Trail (or Track, if you're really that picky). However, this offensive was halted by an Australian-American force.

But what if the Japanese were able to capture Port Moresby?
 
Well, they'll arrive there with a skeleton occupation force via the trail. More substantial troops and their resupply will have to arrive via ship.
 

Loghain

Banned
Imho more Realistic is Capturing New Zealand and holding for Two or three months before they are driven off. New Zeeland is maximum they could have done. There is no way they go to australia
 
Imho more Realistic is Capturing New Zealand and holding for Two or three months before they are driven off. New Zeeland is maximum they could have done. There is no way they go to australia

Invading New Zealand is just as unfeasible, however I wouldn't rule out some sort of 'extended raid' in parts of northern Australia to draw the Allies attention away from a Japanese advance on Fiji or New Caledonia.
 
Imho more Realistic is Capturing New Zealand and holding for Two or three months before they are driven off. New Zeeland is maximum they could have done. There is no way they go to australia

New Zealand is just a logistical impossibility for Japan. Even a carrier raid seems fairly far-fetched.
 
Although the Japanese never planned to invade Australia, they did plan to isolate it from the rest of the world and perhaps, bully it into giving up the war. As part of their strategy, they landed troops on the then-Australian territory of Papua and attempted to capture Port Moresby by going through the Kokoda Trail (or Track, if you're really that picky). However, this offensive was halted by an Australian-American force.

But what if the Japanese were able to capture Port Moresby?

There's no way Japan, which was at the end of its logistics limit in Papua New Guinea, would be remotely capable of isolating the continent from the rest of the planet. Even today Port Moresby hasn't the facilities to do much of anything. I think they were more concerned with keeping PNG out of American hands as it could serve as a stepping stone to retaking The Philippines and Indonesia.
 
Imho more Realistic is Capturing New Zealand and holding for Two or three months before they are driven off. New Zeeland is maximum they could have done. There is no way they go to australia

okay we just went from Japanese capturing Port Morseby to them invading New Zealand... That escalated quickly.

Anyway how is that more realistic? They were nearly at Port Moresby, but far far away from New Zealand.
 

Loghain

Banned
okay we just went from Japanese capturing Port Morseby to them invading New Zealand... That escalated quickly.

Anyway how is that more realistic? They were nearly at Port Moresby, but far far away from New Zealand.

i meant that That is the most you can get Without ASB and even the it would require massive ammount of luck. and i dont mean isolating continent just set up some Airbase on new zeeland. It would require Almost ASB luck to get to New Zeeland. Getting to Australia THAT IS ASB Multipled BY ASB
 
Although the Japanese never planned to invade Australia, they did plan to isolate it from the rest of the world and perhaps, bully it into giving up the war. As part of their strategy, they landed troops on the then-Australian territory of Papua and attempted to capture Port Moresby by going through the Kokoda Trail (or Track, if you're really that picky). However, this offensive was halted by an Australian-American force.

But what if the Japanese were able to capture Port Moresby?
They would be able to launch attacks against Australia. Most significantly, this could have affected Australia’s tenuous supply line to the United States. From Port Moresby, Japanese aircraft and submarines could have exacted a heavy toll on allied shipping, depriving Australia of essential supplies and resources.
 
They would be able to launch attacks against Australia. Most significantly, this could have affected Australia’s tenuous supply line to the United States. From Port Moresby, Japanese aircraft and submarines could have exacted a heavy toll on allied shipping, depriving Australia of essential supplies and resources.

Wouldnt that have actually required them to focus on commerce raiding instead of MUH DECISIVE BATTLE!
 
i meant that That is the most you can get Without ASB and even the it would require massive ammount of luck. and i dont mean isolating continent just set up some Airbase on new zeeland. It would require Almost ASB luck to get to New Zeeland. Getting to Australia THAT IS ASB Multipled BY ASB

but the OP isn't talking about getting to Australia. He's talking about getting to Port Moresby.
 
Ok, a few thousand surviving Japanese soldiers have arrived on the airfields near Port Morsby & occupied the docks. The port, such as it was is even further from Rabaul by sea than Guadalcanal. And, closer to Allied bases. If the Allies still own Guadalcanal it will be fairly easy for them to attack cargo ships attempting to reach Port Morsby & any japanese warships heading that way will be expose to attack from Guadalcanal.
 
and i dont mean isolating continent just set up some Airbase on new zeeland. It would require Almost ASB luck to get to New Zeeland.

First, it's New Zealand, not New Zeeland. Second, I wonder if you've looked at a map recently? It's well over 2000km between the two countries at the closest point. Which means that G4M bombers and A6M fighters might manage the trip one-way, but they will not be conducting regular raids. Frankly, I can't see why the Japanese would want to invade NZ - its strategic importance is negligible, it can't be used as a naval or air base for attacks on anything that is actually important, and since the economy was based heavily on primary resources (mainly agricultural) you still have to get anything useful back to Japan across over 9000km of the Pacific. It just doesn't seem like a good use of scarce military resources. I mean, I'm not sure we even had Marmite back then!
 
They would be able to launch attacks against Australia. Most significantly, this could have affected Australia’s tenuous supply line to the United States. From Port Moresby, Japanese aircraft and submarines could have exacted a heavy toll on allied shipping, depriving Australia of essential supplies and resources.

Except IJN doctrine didn't focus on merchant interdiction, and they were never terribly effective at it as a result. Even staging out of Guadalcanal and Port Moresby, Japanese bombers wouldn't have the range to interdict shipping out of southeastern Australia.

The advantage of seizing Port Moresby is more that it denies a foothold in New Guinea to the Allies, and keeps them farther away from IJN supply lines.
 
To comment briefly, seizing Port Moresby would spare the japanese the debilitating attritional battle in New Guinea that happened from 1942 up to 1944. They can mount various harassing air attacks against australian targets, maybe even commando raids. They would have major airbases at Milne Bay, Buna-Gona area and of course PM (which will probably function like an advanced base) from which to control the waters around New Guinea. As for supplies, that would be their least worry, they can carry supplies on the overland track using slave labour if necessary, while shipping convoys will be relatively unmolested in their trips to northern New Guinea areas.

Allied landings in NG can't happen before second half of 1943 in this scenario imo. What is the distance from Port Moresby to nearest major airfields in Australia?

But really for this to happen imo Midway has to happen differently, and perhaps no Guadalcanal campaign in the first place (the japanese troops and resources used there being instead redirected to New Guinea)- or at least a relatively quick japanese victory at Guadalcanal.
 
Although the Japanese never planned to invade Australia, they did plan to isolate it from the rest of the world and perhaps, bully it into giving up the war. As part of their strategy, they landed troops on the then-Australian territory of Papua and attempted to capture Port Moresby by going through the Kokoda Trail (or Track, if you're really that picky). However, this offensive was halted by an Australian-American force.

But what if the Japanese were able to capture Port Moresby?

Logistically if would be very difficult to hold. Kokoda is one of three divisional sized battles in this region.

Milne Bay would need to fall as well to get the ships through to Moresby. Remember the whole reason for the Kokoda campaign was the loss of the Battle of Coral Sea.

Japan would face a similar position to the British in Crete. The port is on the far side of the island and ships have to run through a narrows then foreign dominated waters. Like Crete there is not an effective overland supply path.

A catch -22 situation. Ships need to reach Moresby to supply enough logistics to support an airbase,
and you need a working base to provide aircover to ships to get them through!

Assuming Milne Bay does fall, it becomes the linchpin to both the Solomans and PNG. From here air power can project west and south to allow sea supply Moresby, and interdict Allied sea traffic the Solomans.

The goal of isolating Australia is naive to me. Even if Japan were successful all the way south to NZ, shipping we just move further and further south. Japan is more and more "out on a limb", ready to cut off.

The only way I can see Japan successful is NOT TO attack the US, by-pass the Phillipines. They can kick Britain /Commonwealth when its down and get there imports of oil, rubber and so forth.

While not comfortable having a base beside your LOS, until the US re-arms, they do not have the assets for anything more than a "passive defence". No major attack are possible from here.

Without the USN, there would be no Coral Sea, no Kokoda, instead a landing at Moresby, Milne Bay cut off. No Midway, and Solomans falls totally to Japan.

IJN has all carriers and BBs to attack Australia were and when it wants. The real question is when the USA would finally break out of isolationism, under the threat of Japan's huge empire?
 
OK the Japanese win the battle(s) and get over the Owen Stanley Mountains. Exactly how many Japanese are now ready to march on Port Moresby? How much ammunition do their have or food. All supplies for this march and attack have to come over the trail, so their logistics suck. The Allies can reinforce Port Moresby without interference, and the Japanese forces approaching Port Moresby will be under air attack with no defense, and the waters between Australia and New Guinea are controlled by the Allied Navies and airpower. Even if the Japanese do take Port Moresby the Allies will have the opportunity to wreck facilities - and any repairs will have to be performed with hand tools. Until the Japanese can land supplies by sea the troops in Port Moresby will be on their own. Even if the Japanese can fly in some aircraft after repairing the fields, how do they resupply with gasoline, ammunition, and bombs to contest Allied air forces. The answer is they can't, even if the Japanese use every transport aircraft they own they can't sustain an aviation element in Port Moresby. In fact, between the track and air supply they will be lucky to provide enough food and ammunition to sustain the garrison.

If the IJN wins Coral Sea and the IJA takes Port Moresby then it becomes a viable outpost - but no more. Annoying raids to N. Australia, but once the Allies build up air power in N. Australia and close the sea lanes it simply becomes a place where the Jpanese slowly starve.
 
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