Japanese not as good at island conquests in WWII as US?

Factual Questions
1

There was a program on the History Channel the other night about Wake Island. From the sounds of it, the Marines put up quite a fight against the Japanese before throwing in the towel.

Later on, when the US re-took many of these islands (I know they bypassed Wake itself but I mean other islands) it seems like while they did suffer casualties in retaking them, it wasn’t as bad as the Japanese initial invasions.

This surprised me. I would figure that the Americans, more willing to surrender if the situation looked hopeless, would mean the Japanese invaders would suffer comparatively less casualties rather than the other way around, where American invaders had to often seemingly kill Japanese to the last man just to completely liberate an island.

Was the ‘island hopping’ tactic really that effective in weakening these little ocean fortresses? I imagine even a significant and fanatical island garrison wouldn’t be terribly effective if deprived resupply for months/years on end. Or is it more a matter of raw numerical superiority (i.e. when US invaded Japanese occupied islands they did it with more overwhelming force)?

2

A major component of MacArthur’s strategy was denial of resources: matereil, food, ammunition, reinforcements. This, to certain extent, softened the fight. But the Japanese pretty much fought all the way down.

3

A lot of factors. When the marines were defending Wake there was a relief task force headed to wake, which was recalled. Also they knew that the longer they held out the more it would slow Japans advance. Aalso the Japaneese did not think the Americans were going to be much of fighters. They considered themselves the superior race and fighter.

When the Americans were invading they understood that they were up against a tough enemy. So they hit with everything they could. In the early invasions they did not use as much Naval guns as later invasions. The US and others learned from their mistakes.

The Island hopping did work. Example Iwo Jima was invaded with a major loss of American lives. Iwo Jima gave them the air field they needed. The next Island was mainly good for an early worning systems. But the US had picket destroyers so the island was passed up and the only Americans to loose their lives there were pilots who crashed there on the way to and from Iwo Jima and were capturred by the Japaneese.

4

The Japanese invasion of Midway was the only failed amphibious landing (in the sense that the island was not seized as planned by the attacking forces) by either side in the Pacific theater. So the Japanese did not have quite the record the US did, but they came close. Amphibious landings were difficult and expensive, they were used because they were also highly successful.

5

Also, Wake was very early in the war, the tactics were still being sorted out.The Americans had a lot of trouble at Tarawa, for example, one of their first tries, primarily because of poor understanding of the way the tide would interact with a barrier reef.

6

Pssst: The Port Moresby invasion force got turned back as well.

Remeber that the Wake invasion occured early in WW2, when neither the Japanese, nor the Americans, had garnered much experience in landing on a hostile beach.

At Guadalcanal, the American pre-invasion bombardment was much shorter than that employed at Tarawa, and then Iwo Jima years later.

The Japanese did not have quite as much heavy weapons in the Table of Equipment (TOE) in their infantry units of the time, as compared to a fully equipped US Army or Marine unit of the same “size”. The Japanese intended to keep their individual soldiers more mobile in rough terrain, that is, terrain compared to what may be found in the western European theatre.

Armored vehicles in the Japanese Army was (and remained) woefully underdeveloped.

The Japanese emphasized “fighting spirit”. The Americans emphasized brute force and copious supplies.

Surprisingly, the Japanese did not adapt as well “on the fly” when “the plan” (mission objective) got derailed (from the statements given by H. P. Willmott in “Empires in the Balance”). Accoding to him, campaign objectives were planned and detailed out at a higher level of command on the American side compared to the Japanese. This provides the benefit of having whatever reserve forces (air support, naval gunfire, reserve troops, and quick resupply in critical areas) that might be available to respond quicker, and on less of a FUBAR basis.

Again, H. P. Willmott states that while their is no questioning the individual bravery of the fighting soldier, the Japanese Army as an organisation was not as flexible as the Allied commands.

He also mentions that the Allied field medical doctrine was better developed as well, leading to somewhat fewer deaths from wounds or diseases than the Japanese would have suffered under the same conditions.

7

I came in here to more or less write what mlees wrote.

The Japanese never developed the tactics and technology for amphibious landings on a hostile beach like the U.S. did-- the latter had to, out of necessity.

As brave as they were, the Japanese foot soldiers in the Pacific were generally woefully understrength and undersupplied. The best army elements were generally fighting in China.

The Japanese Navy, on the other hand, was the skilled equal of the U.S. Navy, at least in the beginning of the war before losses took their toll.

8

Even if they’d been available, it might not have helped.

The odd thing about the Japanese in WW2 is that they were only OK. Their performance was decidedly mediocre in almost every area - in air power, they were prewtty good. But their naval forces performed only acceptably, and their ground forces were not that impressive. They rarely won without having huge advantages. In China, they fought so brutally and yet erratically that they arguably made the resistance, while being ineffectual in a way that the U.S. was not (even in Vietnam). Their assaults on the Soviets were disastrous.

A lot of this apparently came down to being foolishly gung-ho. Despite frequent characterizations abroad that Americans are balls-to-the-wall go-getters, we tend to think pretty coldly before making military assaults. The Japanese were extremely aggressive tactically and strategically, and it cost them on both ends.

The Germans too, to a great degree, although their military command was both more unified and more experienced.

9

I have read that the Germans, and to some degree the Japanese, noted one signficant difference. In heavy battles with huge losses on each side, they found out if their officers were killed or wounded, the troops had great difficulty in contining.

The Americans, OTOH, were much more versatile. If a company commander and all other officers were casualties, a sergeant would take over, and even down to corporals or some Pfcs could assume leadership and were able to continue the fight.

10

The Japanese on the ground were also fighting with inferior weapons. The History Channel sometimes runs some shows on the hand weapons the troops were using. The Japanese had inferior weapons and less ammo. Island hopping by its nature picked out one of several equally well defended targets and hit them with an enormous assault, cutting off the non-attacked targets from future supplies. By the time this got to Iwo Jima, Saipan and Okinawa the Japanese were fighting against overwhelming force with suicidal fanaticism. They were still not going to win, but they made it very costly.

11

Reminiscent of the French in the early part of WWI (“we don’t need the big guns and reserves, we’ve got fighting spirit (elan)”).

12

Another factor was that the Japanese command system was about as screwed up as anything that could have been invented. For all practical purposes, nobody was in overall charge. Everyone was nominally subject to the Emperor but due to traditional restraints he would not actually give orders. So in reality there was nobody who was in a position to run the Japanese war effort. The Army didn’t listen to the Navy, the Navy didn’t listen to the Army, and neither listened to the government. Even within the seperate branches of the military there were large groups that only nominally accepted orders and were largely autonomous. The result was that the Japanese couldn’t co-ordinate their military and concentrate their forces.

13

The Japanese routinely wasted their superb defensive preparations by pointless banzai charges, so that they could die for the Emperor. The only case where the Japanese commander forbid this kind of stupidity was Iwo Jima, which not coincidentally was the only one where the Japanese achieved their aim of killing more Americans than they lost themselves (22,000 vs 28,000). Their intent in the island campaign was to exhaust the American will to fight and manpower but they were their own worst enemy in this regard.

Actually it was exactly the opposite. The Germans noted when the first fought the Americans in North Africa, all they had to do was kill a commanding junior officer and his unit would retreat as they had no idea what to do. In the German army every man was trained to take over the role of his immediate superior and German units routinely fought on in the face of casualties that the Allies would blanch at.

Similarly in Normandy, they noted that often all they had to do to a small American unit was to demonstrate that they had it surrounded and it would often surrender, whereas the experienced Germans knew that their comrades would soon be mounting a counter-attack to link up to them again.

The American army in WWII had a lot of good fighting qualities, but superior versatility, in the sense you use it, was not one of them.

14

This is going farther off-topic, but that’s not what the tabletop simulation game Squad Leader said. According to SL, US forces broke more easily but rallied more easily than Axis forces, because of more “resilient” morale.

15

Who decided the Marines would lead battles in the Pacific and the Army lead in Europe? Was that FDR or someone in the Pentagon? I guess it made sense to split the forces that way.

I could be wrong but now I don’t think the Army does any more beach landings, that is all done by Marines.

16

Banzai charges were suicide attacks by troops who prefered to die attacking rather than risk capture.

17

The basic difference between Japanese and US invasions in the Pacific theater comes down to preparation for attacking defending beaches. In most of the early Japanese successes in the Phillipines, Malaya, the Dutch East Indies, New Guinea and the Solomons the Japanese forces did not attack well-defended beaches. They landed against little or no opposition and consolidated their forces, and then advanced against Allied positions. In Malaya, for example, the explicit strategy of the British defenders was to concede the initial landings and defend prepared positions between the landing sites and Singapore.

Wake Island, however, was too small to allow bypassing defended positions. Compounding this, the first landing attempt was pretty half-assed. The Japanese planners expected the Marines to surrender with minimal fighting, so they didn’t provide the necessary landing support. The pre-invasion bombardment was minimal, there were no aircraft carriers or even seaplane carriers to provide air cover, the troops were not provided with combat-loaded stores, the landing craft were abyssmal, etc.

In contrast, even the costly attack on Tarawa was better-prepared for attacking a defended beach. The lessons learned there were then used to make the later invasions even more successful.

If the Wake invasion had been as well-planned as the attack on Pearl Harbor, it would have been a different story (although ultimately the same outcome).

So basically, the reason for the different experiences is that the US forces had to develop a robust amphibious doctrine for attacking defended beaches, and the Japanese mostly avoided that necessity.

18

In WWII, “the Pentagon” was the location of the War Department, the separate Navy Department was located off Constitution Ave. in downtown D.C. The War Dpartment and Navy Departments were separate Cabinet-level departments, and not sub-Cabinet components of the Department of Defense as they are today. This is a long way of saying that there was no person in the Pentagon that had authority to decide on their own the division of effort between the Army and Navy.

The decision was ultimately Roosevelt’s to make, but he essentially endorsed pre-war understandings that the State-War-Navy committee and other bodies had arrived at. The maritime nature of any coming conflict in the Pacific was clear to all concerned, so the Navy was always going to play the leading role in that theater. The land-based nature of warfare in North Africa and Europe was likewise clear.

The actual structure of the jioint commands was initially a compromise between the Army Chief of Staff George Marshall and the Commander-in-Chief of the United States Fleet Ernest King. This was then formalized into policy.

19

The Army had a substantial presense in the Pacific. Of the 91 Army divisons active during the war, 22 were deployed in the Pacific theatre. In comparison, the Marine Corps consisted of six divisions, all of which were deployed in the Pacific (although there were some small Marine units deployed in Europe).

20

This is pretty much what I was going to say. Not so much casualties, perhaps, as disarticulation. Apparently one german corporal or whatever plus five random guys from other units was often capable of organising into an ad-hoc combat unit and carrying on the fight, whereas a complete squad of allied troops with no NCO or officer would often drop out of action because they’d hunker down and wait for someone to show up and give them orders.
Allegedly down to the fact that the Heer in the '30s made an early start on breaking down the officer/cannonfodder distinction - having junior officers live and train alongside the grunts, and so on.