When to Island Hop vs When to Fight

[Aerosol2207]

I am playing Dec 8 Campaign and am in September 1942.

I opened my first offensive with an invasion of Milne Bay, defended by the 71st IJA and a few base units. I used the 32nd ID and 7th Australian Div. Came off without a hitch, was shocked given that KB is still out there and due to the proximity of Rabaul. I had put in a potent naval air base in at Tagula Island which gave me control of the sea lanes, and supported the invasion with my 3 x USN CV which is all I have left for now. I think I lost a single AP (due to a night time surface action by an intrepid TF of 1 x CL with 2 x DD... which were subsequently sunk on their way out of the invasion area in the AM air phase thanks to my Tagula-based Dauntlesses.).

As soon as my Milne invasion force got ashore, I gained the upperhand and through 2 weeks or so of bombardments I have grinded them down to where the Assault Value is 3 to 1 in my favor and I am contemplating a deliberate attack to finish them off.

All that to say, I feel like I overestimated the IJA at Milne and am now wondering about an earlier decision I made.. which was to bypass Guadalcanal.

I have picked up on the presence of the 17th Army, my recon consistently shows ~31k troops there.. and of course there is the history behind it which leads me to believe that is where the AI is expecting a fight. So I figure... why do this? Why not focus on Tulagi and work my way up from there as needed, making New Guinea the main effort before culminating with New Britain / Rabaul? What do I lose by leaving an intact 17th Army in my rear? If I envelop their position by taking the other islands and eventually Rabaul do they not become prisoners there essentially? Help me plan .

[RangerJoe]

I am playing Dec 8 Campaign and am in September 1942.

I opened my first offensive with an invasion of Milne Bay, defended by the 71st IJA and a few base units. I used the 32nd ID and 7th Australian Div. Came off without a hitch, was shocked given that KB is still out there and due to the proximity of Rabaul. I had put in a potent naval air base in at Tagula Island which gave me control of the sea lanes, and supported the invasion with my 3 x USN CV which is all I have left for now. I think I lost a single AP (due to a night time surface action by an intrepid TF of 1 x CL with 2 x DD... which were subsequently sunk on their way out of the invasion area in the AM air phase thanks to my Tagula-based Dauntlesses.).

As soon as my Milne invasion force got ashore, I gained the upperhand and through 2 weeks or so of bombardments I have grinded them down to where the Assault Value is 3 to 1 in my favor and I am contemplating a deliberate attack to finish them off.

All that to say, I feel like I overestimated the IJA at Milne and am now wondering about an earlier decision I made.. which was to bypass Guadalcanal.

I have picked up on the presence of the 17th Army, my recon consistently shows ~31k troops there.. and of course there is the history behind it which leads me to believe that is where the AI is expecting a fight. So I figure... why do this? Why not focus on Tulagi and work my way up from there as needed, making New Guinea the main effort before culminating with New Britain / Rabaul? What do I lose by leaving an intact 17th Army in my rear? If I envelop their position by taking the other islands and eventually Rabaul do they not become prisoners there essentially? Help me plan .

Lunga will be a good training ground for level bombers as well as bombarding ships.

[Aerosol2207]

I actually got some good experience for my land based air in the Milne Bay operation. Had 4 or 5 B-24/B-17 squadrons flying out of Townsville and some A-20/B-26 out of Tagula. My sense is they are contributing a lot more to the success of the fighting there then the casualty reports during the turns would suggest.

But as for Lunga, do I lose anything by bypassing it? Aside from combat experience opportunities. I am struggling to see how the 17th Army can hurt me if i get control of the surrounding airspace and sea lanes. Will they sneak around the the Solomons on barges if I leave them be? Seems more like a player tactic if thats even feasible.

I am still undecided between coming straight in at Shortlands and sort of pinching the snake at the head i.e. at the top of the island chain, and just biting the bullet with 3 x divisions and committing to a slog on Lunga. The only reason I am even entertaining it is because of how well my 2 fairly mediocre divisions have done at Milne. I was expecting the divisions there to basically be ground down to dust. But it looks like while I will be up against a larger force (with added bonus of an IJA Army HQ unit on the island), I should be able to win with 2 x USMC divisions plus the Americal boys. Tough call.

[Bella]

I am playing Dec 8 Campaign and am in September 1942.

I opened my first offensive with an invasion of Milne Bay, defended by the 71st IJA and a few base units. I used the 32nd ID and 7th Australian Div. Came off without a hitch, was shocked given that KB is still out there and due to the proximity of Rabaul. I had put in a potent naval air base in at Tagula Island which gave me control of the sea lanes, and supported the invasion with my 3 x USN CV which is all I have left for now. I think I lost a single AP (due to a night time surface action by an intrepid TF of 1 x CL with 2 x DD... which were subsequently sunk on their way out of the invasion area in the AM air phase thanks to my Tagula-based Dauntlesses.).

As soon as my Milne invasion force got ashore, I gained the upperhand and through 2 weeks or so of bombardments I have grinded them down to where the Assault Value is 3 to 1 in my favor and I am contemplating a deliberate attack to finish them off.

All that to say, I feel like I overestimated the IJA at Milne and am now wondering about an earlier decision I made.. which was to bypass Guadalcanal.

I have picked up on the presence of the 17th Army, my recon consistently shows ~31k troops there.. and of course there is the history behind it which leads me to believe that is where the AI is expecting a fight. So I figure... why do this? Why not focus on Tulagi and work my way up from there as needed, making New Guinea the main effort before culminating with New Britain / Rabaul? What do I lose by leaving an intact 17th Army in my rear? If I envelop their position by taking the other islands and eventually Rabaul do they not become prisoners there essentially? Help me plan .

IMHO, moving up the Solomon chain towards Rabaul has much more potential than focussing on New Guinea. You can build reasonably large airfields/ports at Lunga, Tassafronga, Tulagi, and Thousand Ships Bay which provide you with immense air cover for amphibious ops as you move into air range of Rabaul. If you include a couple squadrons of Marine Vindicators/Dauntlesses, you also make it prohibitive for the IJN if it tries to do naval raids down the Slot (sank a BB, two CA and a bunch of CL and destroyers in my game.)

Port Moresby/Milne/Buna are not well supportive of each other, being too far apart, and except for Port Moresby, hard to build up. And really (as historian H.P. Wilmott says) New Guinea is essentially useless to the Japanese. Even taking Port Moresby is of little value to them, at extreme air range to Townsville and other NE Australian bases. You can bleed their unescorted air-groups and the occasional KB raid with P-40s and flak.

I’m still fighting for PM, for sure, and using it as bait for my carrier groups to sink Bombardment and invasion fleets, but I’m not going to cry too much if it falls (don’t think it will; put a couple Aussie brigades and other units when I could, and the Japanese must be having supply issues over the Komodo’s Trail, but you never know).

[Aerosol2207]

Thanks Bella. I am a big fan of HP Wilmott as well. I agree that an interconneced series of airbases in the Solomons is preferable all things being equal - but I suppose I am more wondering if the endeavor will be worth it once the Japanese have the whole 17th Army on the island with ~31k troops. Maybe I am overestimating them or underestimating the ability of the force I'd have available - which would be 2 x USMC Divisions and the U.S. Army Americal Division.

Oddly, in my game the Japanese have already built out Lunga to a size 8(!) airfield but I have not noticed significant sorties generated from there. Shortlands and Rabaul remain the beehives of Japanese air activity. I view my strategic objective as 1) capture Rabaul 2) turn the Bismarck and Solomon Seas into an Allied lake. I am undecided whether Lunga is a necessary condition to that.

I like Milne Bay because, in combination with my base at Tagula I can basically "shut the door" between the Bismarck/Solomon Sea and the Coral Sea.

[RangerJoe]

Why capture Rabaul? Why not isolate it and bypass it?

[Aerosol2207]

You know, I don't have a good answer for 'Why capture Rabaul?" come to think of it. I was sort of just by default pursuing it because it is the IJN's center of gravity in the South Pacific / Southwest Pacific theater.

I suppose you could say it should be taken because it could be useful given the size of its port/airfield facilities. Did the Allies in real life make much use out of Rabaul? EDIT to add I remember now they just isolated it despite being on New Britain. Seems like they had gotten such a beefy seaborne logistics capability by that point that they could go direct to the Marianas (skipping Truk).

[RangerJoe]

You know, I don't have a good answer for 'Why capture Rabaul?" come to think of it. I was sort of just by default pursuing it because it is the IJN's center of gravity in the South Pacific / Southwest Pacific theater.

I suppose you could say it should be taken because it could be useful given the size of its port/airfield facilities. Did the Allies in real life make much use out of Rabaul? EDIT to add I remember now they just isolated it despite being on New Britain. Seems like they had gotten such a beefy seaborne logistics capability by that point that they could go direct to the Marianas (skipping Truk).

The Allies developed Milne Bay and Manus as bases.

[Bella]

You know, I don't have a good answer for 'Why capture Rabaul?" come to think of it. I was sort of just by default pursuing it because it is the IJN's center of gravity in the South Pacific / Southwest Pacific theater.

I suppose you could say it should be taken because it could be useful given the size of its port/airfield facilities. Did the Allies in real life make much use out of Rabaul? EDIT to add I remember now they just isolated it despite being on New Britain. Seems like they had gotten such a beefy seaborne logistics capability by that point that they could go direct to the Marianas (skipping Truk).

The Allies developed Milne Bay and Manus as bases.

There is a YouTube short about Milne Bay in ‘42. It was such a hole. Jungle hot, tons of malaria, living in mud, and they could only fly using airfield matting which essentially acted as a floating tarmac. It had huge ripples in it as a/c landed and took off, with cresting waves generated by the surging matting. Ridiculous.

[Bella]

You know, I don't have a good answer for 'Why capture Rabaul?" come to think of it. I was sort of just by default pursuing it because it is the IJN's center of gravity in the South Pacific / Southwest Pacific theater.

I suppose you could say it should be taken because it could be useful given the size of its port/airfield facilities. Did the Allies in real life make much use out of Rabaul? EDIT to add I remember now they just isolated it despite being on New Britain. Seems like they had gotten such a beefy seaborne logistics capability by that point that they could go direct to the Marianas (skipping Truk).

Yeah, Rabaul and it’s garrison rotted and starved until the end of the war. They lived on fish the soldiers caught and rice brought in by submarine.

[dasboot1960]

I'm with Ranger Joe here. The magic word is Manus. You have to do all the prep work even if you invade Rabaul, then just don't. Plunk it down at Manus. You'll have air basing within weeks, his guys are trapped, and you didn't lose the casualties. Milne or something like it on islands, is part of the Rabaul prep. There's plenty further on you have no choice but to fight over. It's all hop. Cheaper's better. By that time, you might have a better stance toward KB.

[Chickenboy]

What the others said re: bypassing Rabaul if possible.

There is an important consideration to advice for you though. Are you playing against the computer or human PBEM? The mechanics of how bypassed garrisons starve / rot on the vine (against a human player) are different versus a computer player (it basically won't ever starve out).

On the other hand, you can probably develop any number of bases surrounding Rabaul and the AI will be unlikely to react as a human player would (i.e., violently).

FWIW, the 'island hopping' idea really originated in the SW Pacific by the USN/USMC/USA in the Solomon Islands campaign and later by MacArthur in PNG. So it's absolutely historical to consider doing so in your game as Allies.

[PaxMondo]

What the others said re: bypassing Rabaul if possible.

There is an important consideration to advice for you though. Are you playing against the computer or human PBEM? The mechanics of how bypassed garrisons starve / rot on the vine (against a human player) are different versus a computer player (it basically won't ever starve out).

On the other hand, you can probably develop any number of bases surrounding Rabaul and the AI will be unlikely to react as a human player would (i.e., violently).

FWIW, the 'island hopping' idea really originated in the SW Pacific by the USN/USMC/USA in the Solomon Islands campaign and later by MacArthur in PNG. So it's absolutely historical to consider doing so in your game as Allies.

As usual, CB has hit the nail square on the head. First, and most important, question is: is this AI or PBEM game?

AI doesn't react well to hopping, particularly important bases like Rabaul. So, against the AI, you need to pursue taking Rabaul to keep your game going.