Japan Naval Defense
Written by uffishbongo on 06-03-2009 at Axis and Allies.org forums
This is a collection of thoughts about how Japan can defend against the US navy. It’s long enough that it’s more like an article than a regular post; I hope that’s not too pretentious.
The topic of this article is how to respond to a particular Allied strategy that I think is fundamentally flawed, but that I nevertheless come up against regularly in league play. I suppose that by trying to convince people to stop using a flawed strategy against me, I’m not really doing myself any favors. What can I say, I’m just that magnanimous. tongue Ideas from this article could of course be applied to other situations, but a lot of the specifics will be different.
The strategy I have in mind is one in which the UK and Russia go against Germany, and the USA goes after Japan. Theoretically it might be possible for the US to do this with a Sinkiang complex plus navy, but without Russian help the complex is doomed, so play generally proceeds by getting into a naval arms race with Japan. The primary objective is to out-build Japan’s navy enough to go island-hopping and secure a decisive income advantage. Once that’s been done you can kill Japan’s navy, push them off the mainland, etc. A secondary objective would be for Japan to spend all its money on boats in order to stay ahead, relieving any Japanese pressure against Russia and enabling them to put all their troops on the German front.
It’s about time for some disclaimers:
(1)This strategy can be OK _in response to specific game events_ , by which I mean, if Japan eats crow in Pearl and allows you to wipe out two of their capital ships on USA1. But if Japan comes out of J1 with its whole navy and air force intact and a strong Pearl and you take this approach anyway?which I’ve seen happen plenty of times!?you are trying to climb a very steep mountain.
(2) I’m not trying to say that KJF is bad in general. What I am trying to say is that if you want to go KJF, go all the way. Use all three Allies and hold nothing back. If you go half against Germany and half against Japan, it’s not enough, unless the dice are very kind to you.
***TWO KINDS OF DEFENSE, AND NAVAL BUILD STRATEGIES***
There are two kinds of defense in A&A. The first, which I’ll call ?survival?, is making sure your stack is powerful enough on defense to survive if attacked. The second, which I’ll call ?buffering?, is making sure your stack has enough offense that the enemies don’t dare move within range. It’s usually preferable to play the second kind of defense when possible, and fall back to the first only when you must. This keeps your income higher, and reduces the danger to your critical territories.
Which kind of defense you’re playing affects your purchasing strategy. If you want to play the more aggressive form of defense, the key statistic is the *attack* power of your units, not their defense power. Conversely, your aggressor’s ability to advance on you is based on the *defense* power of his units, even though he’s the one going on the offensive. So everything is kind of backwards.
One specific way that this affects purchasing strategy in the water is how many fighters you buy per carrier. If you’re going for survival-defense then you want two fighters per carrier. However, if you’re going for buffering-defense then you want four fighters per carrier. This is because an attacking carrier can usually support four fighters, provided there is land reasonably close by: Two fighters start on the carrier, attack the sea zone, and then land on a nearby island or continent, while two fighters do the reverse (start on land, attack the sea, and land on the carrier).
***BATTLE STATISTICS AND PURCHASING STRATEGIES***
Suppose you and your opponent are both given $10,000 to buy the most powerful navy you can. What should you invest in? Subs? Carriers and fighters? Battleships? Some kind of mix? What gives you the most bang for your buck? Well, this is where it gets mathematical…if your eyes glaze over, just skip to the parts in all caps. wink
There are three statistics that measure how powerful a given army is: punch, count, and skew. The punch is the sum of all the attack values of the attacking units, or defense values of the defending units. (Your expected number of hits will then just be your punch divided by 6. For example, 3 inf 3 tanks attacking have a punch of 12 and will get 2 hits in an average round.) The count is simply how many units are in the army. Skew is harder to quantify, but it has to do with how ?spread out? your combat values are; if you have some high-power and some low-power units it’s generally better than a bunch of mid-range units. (For example, 100 inf 100 tanks attacking 200 inf will almost always win, even though their punch and count are identical. This is because the attackers can take some hits without losing power as fast as the defenders).
So how does all that math affect purchasing strategy? Well, one simple way to proceed is to calculate which purchases give you the most punch per IPC. Unfortunately this won’t account for count and skew, but some hand-waving descriptive arguments can help figure out how those factor in.
At first glance, here are the stats:
The moral of the story seems to be that both sides should just buy fighters. Unfortunately, one quickly realizes that without carriers this doesn’t actually help your navy much! A more relevant statistic would be to compute punch/IPC for a *carrier group*, meaning a carrier plus all the fighters it can support. Recall that a defensive carrier group consists of a carrier with two fighters, whereas an offensive carrier group consists of a carrier with four fighters. We then have the following revised table:
So, what to make of this? If you’re looking to go on the offensive?or, if you’re looking to go on the defensive using the buffer method?then carriers and fighters are slightly less efficient ways of getting punch than subs, destroyers or bombers. When you factor count into the equation?an offensive carrier groups costs $56 for 5 units, whereas you could get 7 subs for the same price?it becomes clear that subs are your best bet for adding to your offensive punch. However, on defense the picture is not so clear. Carrier groups give you significantly more defensive punch per IPC than subs do, but subs give you significantly more count (50% more, in fact). Tough call. Personally I would still go with subs as my mainstay, since their count advantage seems to be wider than the carrier group’s punch advantage.
The other moral of the story is that, just as in the land war, defensive punch is cheaper than offensive punch. This implies that if you and the Americans spend the same amount of money, given long enough they will eventually reach the point where they can safely advance within range of your navy. Of course, with your initial head start that may take a while, by which point your income could be higher than theirs due to gains in Asia. But it is good to know that the long-term situation favors their ability to push forward if all other things are equal.
But wait, there’s more! Why did I leave the solo fighters on the list? Didn’t we decide they were just a fiction? No, there are circumstances where their statistics are relevant. Considering the following two applications:
(1) MAX OUT YOUR EXISTING CARRIERS FIRST! If you already have a carrier and you don’t have all the fighters for it, then buying more fighters to fill it up is effectively adding to your army at the solo fighter rate rather than the carrier-group rate. The application to Japan is, BUY YOUR 8TH FIGHTER BEFORE GOING HEAVY ON THE SUBS. With your two initial carriers you can bring 8 fighters to the battle. Until you have those 8, more fighters are the fastest way to add to your offensive punch.
(2)If you station air on an adjacent island, the fighters don’t need a carrier. For instance, if you’re anticipating a big battle in SZ 45, then you can park your air on the Caroline Islands and it’ll be two spaces from SZ 45?so, no carrier needed! You can buy as many fighters as you like. So you really can add to your force at the solo-fighter rate. This option is competitive with subs as the best overall offensive purchase; you get 20% more punch than with subs, but 20% less count.
So far I’ve just been considering the effectiveness of different units and purchases in the abstract. Time to look at the geography of how a US invasion might proceed, and how to fend it off.
US INVASION STRATEGY
It’s well known that the favorite US invasion point is the Solomon Islands and its corresponding sea zone, SZ 45. This because (a) it’s only two moves from SZ 55, so US builds can get there in one turn, and (b) it’s within two moves, hence one turn, from all the key islands: East Indies, Borne, Philippines, and even Australia. Thus, a massed American fleet off LA can move to the Solomons in one turn, and then go crazy all over the islands.
As soon as it’s safe the Americans would like to build a factory in either Borneo or the East Indies. This allows them to build ships right in the thick of the conflict. Borneo is a more aggressive option, since its sea zone is only two moves from Japan; the Americans have to be doing pretty well to be able to put that factory up. East Indies is three moves away and hence may be feasible at an earlier point, but of course the flip side is that it puts less pressure on the Japanese navy because of the extra space.
In summary, the basic USA invasion proceeds as follows: move to SZ 45, start taking islands, put up a factory on one of the big islands, and start producing ships in Japan’s backyard.
SIMPLISTIC JAPANESE COUNTERMEASURES AND HOW THEY FAIL
Since the Solomons are the linchpin of US invasions, perhaps the way to counter is just to make sure enough firepower is within reach of SZ 45 to kill anything that moves there. So with Japan you can just mass your fleet in SZ 60, and make sure SZ 45 is a deadzone, right?
The reason this fails is because the US can buffer with a sacrificial lamb. They move most of the fleet to SZ 45, but leave one cheap straggler in SZ 51. All the glorious Japanese battleships are now prevented from attacking, as are the transports you might use for fodder. If the Americans are smart enough to buffer with a destroyer then your subs can’t get there either. Attacking with pure air against a fleet with lots of transports to absorb your hits gets real ugly real fast.
Buffering like this allows the US to invade with an inferior fleet. You can send your fleet down to chase them, but they can grab a few islands, continue to protect their main fleet with a buffer, and put up a factory before you manage to pin them down. Few things are more frustrating than chasing an inferior fleet around the South Pacific while they take your valuable islands from you and continue to send reinforcements in from the east!
BETTER JAPANESE COUNTERMEASURES
In order to avoid this kind of scenario, it’s best to stay far enough ahead with your naval builds that the buffering strategy becomes impossible. The key is to have your main fleet sitting next to SZ 45, not two spaces away, so that the US can’t protect itself with a buffer.
If your fleet is a lot bigger than the Americans’, you could take the offensive and push your fleet up to Hawaii or Wake. However, staying on the offensive in the Pacific will take a lot of your resources, and you’d rather be putting some ground troops in Asia to grow your economy and pressure Russia. Hence, a more economically efficient option is to create a stalemate: you hang back and make them make the first move, but keep enough power to make that move costly. Hence, you want your main fleet buildup to be in a spot that (a) is out of reach of SZ 55 (so you don’t have to worry about your survivability against an American attack?you can guarantee that you’re the one threatening to attack), and (b) is adjacent to SZ 45. This means the Caroline Islands is the place to go.
If you have ships farther west that are within reach of SZ 45?say, SZ 37, or either 38 or 46, or 48, etc?these are still OK because the US can’t reach far enough to buffer against them. It’s really just the SZ 60 fleet that can be made ineffective by a Wake Island buffer. So you can still send your boats to grab Australia, deal with an annoying British fleet in Borneo, or whatever, while still keeping an eye on the Solomons.
However, your default buildup spot is the Carolines. You should park your battleships there, and at least one carrier. Once you’ve built up to your 8th fighter (see above) you will want to start getting some subs in the mix. Build them in SZ 60 and then move them to SZ 50 on the subsequent turn. Note that this requires you to stay a turn ahead of demand, because there’s a turn delay between when you build the subs and when they are (unblockably) threatening SZ 45.
As mentioned above, you can buy beyond your 8th fighter if you plan to station some air on the Caroline Islands. This gives you more punch but less count than subs, so it’s a judgment call. However, this has the additional advantage that your purchases go into effect immediately: If you move an already existing fighter from the mainland to the Carolines (or from the mainland to your carrier and one from the carrier to the Carolines), then your new fighter purchased in Japan is threatening SZ 45 and will have the potential carrier spot opened up to it that was vacated by the fighter you moved to the Carolines. So if you need to up your threat to SZ 45 and can’t wait a turn for your sub purchases to move into position, a fighter purchase can do it more quickly.
You will need to think about defending SZ 60 against air. You’ll probably have a couple transports operating there, and your new sub builds. This makes a juicy target for air in SZ 55; they can go on a raid and move a carrier up to SZ 57 to pick them up. Since this would likely be suicidal for the carrier, it may not be worth their while, but you need to keep an eye out for that move and think about whether to leave some air defense in SZ 60. If the air threat is small, a destroyer should do the trick; if you need more, you can leave one of your carriers there.
Let’s talk about where to station the fighters. Four of them will be on your carriers, able to hit SZ 45 and then land on an island or mainland. The other four, then, can start anywhere within four spaces of SZ 45. This means you can put them as far up as India and Yakut and still be able to make it in four spaces. If you haven’t held India or Yakut yet, or just want to provide more complete coverage of the Pacific, try FIC and Buryatia. Either way, you can keep using four fighters against Russia while still maintaining the threat to SZ 45. A bomber stationed in Buryatia is great too; it can hit the key Pacific spots, can reach all the Russian territories east of Caucasus, and can SBR Moscow, all from the same place.
Sometimes things go wrong. You make a blunder, or the dice get screwy, or whatever. Ideally you’d like to prevent a move to SZ 45, but suppose it happens. Then what?
Well, my favorite fallback spot is FIC. There are two reasons for this. One, I always build a factory there J1 if the Russians and Brits didn’t go bananas with a crazy KJF starter. (My favorite J1 purchase for a KGF game is 2 tran 1 IC after bidding $1.) Second, it’s right next to your three big islands (East Indies, Borneo, and Philippines). You can let the US get Okinawa and New Guinea, those are small potatoes, but you want to protect your big islands.
If you’re forced to fall back, then, the basic maneuver looks like this:
(a) Move fleet to SZ 36, and build up to 3 more ships there (subs most likely, maybe a destroyer)
(b) Build more air in Japan if you have the money for it.
The result is that you can deadzone the three valuable islands. What’s more, because FIC is adjacent, there’s no way for them to use a buffer to sneak in either. So even after they push to SZ 45, you may be able to keep them away from your big targets for a few more turns.
If you do this, MAKE SURE THEY DON’T GRAB TOKYO! Moving your fleet down from SZ 60 to join the others in SZ 36 leaves you open to invasion. Station some air there, and buy a couple inf if you need to.
***SUMMARY: HOW TO REPEL AN ILL-ADVISED AMERICAN FLEET BUILDUP***
–First, make sure it really would be ill-advised. That means not losing your initial fleet. If you go heavy into Pearl on J1, which I still usually do (even though it’s becoming less fashionable these days), make sure you come out with your BB and CV and 2 ftr and one other ship if at all possible. This means attacking with your DD and sub (if it survived) is a good idea, it may mean losing your bomber before a cheaper ship, and if things go wrong you may want to non-combat your transport from SZ 60 to help out. Better to start a little slower on Asia than to lose your fleet.
–Buy up to your 8th fighter soon. Station 4 on your carriers, 4 on the mainland but still within reach of SZ 45. This way you can use them against Russia throughout the naval standoff. Bomber goes on Bry or possibly FIC.
—For the first few turns, you shouldn’t need to buy more boats except some transports. Focus on grabbing land in Asia, while always calculating to make sure you’re deadzoning SZ 45 adequately.
—If the Americans continue to get serious about their naval builds, start getting some subs while continuing to make ground units. Station your main fleet in SZ 50, move your sub builds there the turn after you make them, and keep your 8 ftr within range.
—Consider adding more fighters, to be stationed on the Carolines (or New Guinea), in addition to your sub builds. Also make sure you have one destroyer in SZ 50 to cancel out their sub’s special abilities.
—If you have to fall back from a superior fleet, pull back to SZ 36, build more boats there, build more air on Japan, and make sure to adequately protect Tokyo. This should buy you some more time before your key islands fall.