"Pearl Harbor's Overlooked Answer" Topic

From official investigations to conspiracy theories, efforts to account for how the United States was caught so unprepared on 7 December 1941 have almost all failed to take into account that the attackers were wielding a quickly evolving aircraft carrier force that would revolutionize naval warfare.

USNI: link

We did as well though, AND there was a similar attack more than a year before that could point home the possibility of such a surprise attack on a fleet at anchor.

Seems many were asleep at the wheel, even though we knew the Japanese were unhappy with our actions prior to hostilities taking place.

Also, interestingly, I've never heard a full accounting of how and where our carriers managed to be away from Pearl Harbor, and why (IIRC, there was some sort of exercise with them, south of the islands, I believe). I'd like to know more details about that.

The article's main point is nicely summarized in the article:

"After Taranto, carrier raids with a single carrier were not new. Nor was using a carrier to sink a battleship at anchor. What was new was assembling a huge carrier force, transiting thousands of miles to the objective, and then using hundreds of aircraft in broad daylight to simultaneously crush multiple airfields and a major fleet base. Outside of the Japanese navy, almost no one could comprehend such a massive, coordinated operation."

The only quibble I have with this summary is I doubt that outside of the carrier strike force itself and a handful of leaders, no one in the Japanese navy could truly comprehend
it ( and likely many inside the carrier force). This is well illustrated by how the Japanese failed to use the Kito Butai widely after pearl Harbor. It was 1944 before the US figured it out.

After Pearl the US raided several Japanese bases and the Kido Butai raided into the Indian Ocean and Darwin. I believe the Americans were surprised at Pearl because no one thought it was possible to pull it off over the vast distances involved.

IIRC, the carriers had concluded that exercise and the weather prevented them from being at Peral- that the Japanese were counting on them being there.

Operation Orange (IIRC) AND Fletcher Pratt "proofed" that plan in a wargame before the war. What really needs to be picked apart is why the warning of the imminent Japanese attack was delayed only to be received at Pearl Harbor while under attack! (A real "Well no S*(t" moment if there ever was one!

Thresher01, there were three carriers assigned to the Pacific Fleet.
Saratoga had just completed an eight-month refit at Puget Sound and was at San Diego embarking its air wing.

Lexington was delivering 18 Marine Corps dive bombers to Midway, having left Pearl Harbor on December 5. Her route was well to the south of the Kido Butai.

Enterprise had just delivered Marine F-4F Wildcat fighters to Wake Island and was reached Pearl Harbor the afternoon of December 7. Some of her planes took part in the battle, more or less accidentally.

Using fleet carriers to deliver aircraft may not have been the best possible use of the ships. It does demonstrate what the author says about using carriers individually.

Also, for what it is worth, the coded attack signal sent to Kido Butai on December 2 was "Climb Mount Niitaka." Mount Niitaka was the tallest mountain in the Japanese Empire. It's on the east side of Formosa/Taiwan and is now known as Yu Shan. The peak is 3,952 meters (12,966 ft) above sea level.

Grelber

"Pearl Harbor's Overlooked Answer
From official investigations to conspiracy theories, efforts to account for how the United States was caught so unprepared on 7 December 1941 have almost all failed to take into account that the attackers were wielding a quickly evolving aircraft carrier force that would revolutionize naval warfare."

A politically correct answer and not assigning blame. A case where the Naval Department failed in their job passing along actionable intel to the fighting force in a timely manner. Somebody up high should have been canned! BTW, there were 3 carriers (almost all in the entire US fleet but 100% in the Pacific at the time.)

I think a good analogy to compare with Pearl Harbor is the battle of Isandlwana in the Zulu War, we underestimated the enemy's ability to strike and they were a lot better than we expected!

This is an excellent article (and being from the U.S. Naval Institute Press I wouldn't expect anything else). The point it makes is very important and usually overlooked: the sort of attack the Japanese launched was completely unprecedented. No one had done anything like it before and most people had never even considered it a possibility. Even the Japanese were surprised by how well it went. Defenses are usually set up to protect against known threats. When you get hit by something new, things can turn out very badly.

Parshall and Tully's Shattered Sword, IMO the best account about Midway, covers these same points. While the American communications Issue had immediate impact, I agree with the author that the Japanese had taken the concept of a large powerful naval air strike force to a higher level than anyone else, developed expertise and logistics for it, and unleashed it in an awesome fashion. Even they did not quite understand how they had changed naval warfare forever. With all due respect to the Taranto raiders who inspired the Japanese, Kido Butai brought a new era, not yet fully realized. Suddenly the battleship era more or less ended and a new type of mobile fast strike warfare took hold.

In 1932, Harry E. Yarnell proved that Pearl was vulnerable to a naval aerial attack. 1932.

I think we misunderstood the Japanese intent. A different set of precautions would have been in place if hostilities had been declared. Fortunately, the other side misunderstood US resolve once hostilities had been declared.

I know it is Navy culture to assign blame, but it is akin to holding a murder victim accountable for the felon's offense.

The real story is hidden somewhere within the correspondence that passed (or did not pass) between the Dept of State, the White House, the Joint Chiefs, the Navy Department and Kimmel's HQ @ Pearl Harbor in the days/week preceding 7Dec.

B

The real story is hidden somewhere within the correspondence that passed (or did not pass) between the Dept of State, the White House, the Joint Chiefs, the Navy Department and Kimmel's HQ @ Pearl Harbor in the days/week preceding 7Dec.

Meaning that the article isn't the "real story"?

I have always found the account of bureaucratic rivalry and casual peacetime mentalities and practices (and individual peccadilloes) in Edwin Layton's memoir to be highly compelling.

I believe that this and other similar articles present a number of distortions that end up being perpetuated. This is unfortunate, because there are indeed many things to learn, we just need to make sure we are addressing the right details. A few points for consideration:

1) The US Navy was very aware of the Japanese navy's main carrier force and its general strike capability. We had one, they had one, it was easy to put one plus one together. They studiously attempted to track the IJN's main carrier fleet at all times, but had "lost" them several times that year already. So when they lost them again (when the Japanese changed their code) not long before deployment for the attack, it was not considered unusual, and in any case not something they could immediately resolve other than trying to break the new code and resume tracking.

2) Numerous war warnings were sent to Hawaii in the weeks leading up to the attack. The Japanese navy was known to have put to sea. At one meeting on November 27, the possibility of the Japanese directly attacking Hawaii was considered, but Captain Charles McMorris claimed the odds of them doing that was "…absolutely none." It was discussed in Kimmel's presence however, which leads us to:

3) The US fleet had two main anchorage options for Hawaii: Pearl Harbor and Lahaina Roads. The US battleships were told to return to Pearl instead of going to Lahaina Roads, and it is generally considered (sorry, can't supply references at the moment) that their logic for doing so was that if the Japanese DID attack, it was better not to have any ships sunk in the deep water off Lahaina. So the possibility of an attack was apparently not completely out of their minds.

4) When Halsey took Enterprise out of Pearl on November 28, he did so under the guise of going on maneuvers. After reaching the open sea, he left the battleships and headed west with his cruiser/destroyer escort and sent Battle Order Number One to his task group that said "Enterprise is now operating under war conditions…" He ordered radio silence for the group and began flying fully armed CAP. That is not the actions of a surprised group of officers.

I think it is important to understand what the forces at Hawaii were being expected to do, and to understand the proportion of their various responses. Their main goal at the time was to operate as a through-point for resources headed out to the Philippines, Wake, Guam, Australia, etc. And also to be the ready reserve for any response. They did consider that they might be attacked, but they had to juggle that lesser probability (as considered at the time) against the very high odds of the Philippines being attacked. They did take some basic precautions, one of them being to wisely keep the carriers out of port as much as possible.

It is a complicated series of events that may never be fully understood. Gordon Prange's "At Dawn We Slept" is probably the best single book on the subject.

I think the staffs pretty clearly realized that something was up, but attention in Washington was focused to the west of Hawaii, on the Philippines, Malaya, and the Dutch East Indies. Edwin Layton, the Pacific Fleet intelligence officer, states pretty clearly in his memoirs that they had lost track of the carriers, but they definitely had a read on the ships that were moving south toward the Philippines, which partially explains why the US carriers were so alert as they moved westward- they were sailing toward a war zone, and the Marshalls were a possible location for the Japanese carriers. The last thing they probably expected was that the war would start behind them.

There are a lot of contributing factors to Pearl Harbor (I haven't touched the way decisions about information sharing and intelligence analysis we're getting made in DC), but one underestimated factor is the galvanizing effect of known information- which encouraged everyone to look in the wrong direction, until it was too late.

Agreed, although Halsey was running searches out to 200 miles soon (?) after he had left the battleships behind. That would mean he felt compelled to be on wartime alert while still in Hawaiian waters, so… a few points of credit I guess, compared to some of his co-workers. In 1940, Adm. Richardson specifically warned that the fleet was a target of the Japanese as long as it was based at Oahu.

I recall that another reason for bringing the battleships back to Pearl, was the navy's perception that they would be under the protection of the army air forces (another indicator that an attack was not wholly and completely out of consideration). That whole relationship between the branches had the predictable weaknesses. Rommel once quipped that one of his more difficult jobs was having to constantly remind the army and air force troops that the British and Americans were the enemy!

Ultimately, the Japanese were under orders to fight their way into the area if necessary. So even some of the big "what ifs" like if the Opana radar warning had been forwarded, instead of being stopped by a 28 year old Lt. in the (new) Intercept Center, are not always as earthshaking as insinuated. The Japanese were rapidly approaching and so even if the warning had been forwarded, any response by the American fighters would most likely have prevented the Japanese fighters from having free reign to strafe at will for a while. The fighter's main job was to keep any US fighters away from the bombers, and they would have taken that job seriously.

Interestingly, numerous Japanese air crews who survived the war later reported their shock at how quickly they ran into AA fire. Pilots and radiomen in the first Kate torpedo bomber wave commented how they were already taking anti-aircraft fire from both sides before and after TT launch. One of them specifically noted the difficulty they had dodging the AA fire after their drop, and that five of the seven torpedo bombers behind them were shot down. That is not quite the picture always portrayed in the movies, with their emphasis on ammo being locked-up, etc. Not that we should be using movies as references! But they can affect general perspectives in ways that color opinion.

At some level, the US Army and Navy may have been better prepared for war in 1939 than they were in 1940. By that, I don't mean that they were adequate to the task, just that the rapid changes and initiatives undertaken in 1940-1941 probably actually lowered readiness before they raised it.

A partial list of just some of the bigger changes that the services went through includes:

– Mobilizing the National Guard
– Instituting the draft
– Undertaking significant expansion of the Army and Air
Force
– Undertaking Lend-Lease (which shortened existing stocks)
– Beginning a massive new program of naval construction
– Snap decisions to change major unit basing and posture,
including:
– Forward-basing the fleet at Pearl Harbor from 1940
– Reversing twenty years of Philippine defense policy in
the summer of 1941
– Dispatching major land and air reinforcements to the
Philippines to make that policy viable, and to
establish an air striking capability

Each of these individually would have been a seismic shock for the services (particularly the Army), but together they represented the biggest national mobilization American had undertaken since the Civil War. Everything was in short supply, teams and crews where in chaos as they attempted to digest draftees and reservists, senior officers were changing positions rapidly, and every ready aircraft and ship was moved to the spot where it appeared to be most immediately needed, as the need arose – and in the summer and fall of 1941, the Philippines looked like the point of greatest vulnerability. In a sense, it was: the Japanese took it shortly after Pearl Harbor, something they probably could never have done with Hawaii.

The forward basing of the Pacific Fleet was meant to deter Japan, but its war plan (WPPAC-46) reflects the degree to which logistical and training constraints limited its range of action. The plan envisioned air strikes at the Marshalls in the hope of drawing Japanese ships out for a surface engagement and – not much more. There was no serious short-term plan yet for a Central Pacific campaign, because at the time, the services were in no position to do much more than prevent a Japanese advance on the West Coast. The war started two years before the US was really ready to wage it to a successful conclusion, and that itself explains a lot about why the truly "decisive operations" that were intended to break Japan and Germany were not launched until late 1943 (Central Pacific offensive) and mid-1944 (D-Day).

That being said, one other factor strongly influenced the general imaginative failure that made Pearl Harbor such a surprise: even if it was a success, the power differential between the two sides was so lopsided that the Americans had difficulty believing that a rational decision-maker would choose to take on every major power in the Pacific simultaneously, even if the short-term outlook was unfavorable for the defenders. The list of people who said, "they would never DARE" in the weeks before Pearl Harbor is pretty long and includes some pretty distinguished senior commanders.

One other major factor that doesn't get enough attention was the almost total dependence on signals intelligence to monitor Japanese movements and intentions, and the degree to which the intelligence system was unbalanced, with a pronounced tilt toward the technical elements of gaining information (collection, decryption and codebreaking, and translation), rather than the analysis of that information. The centers to collect, collate and analyze the raw information provided by that technical process wouldn't exist until after Midway, and most of the people who were in charge of intelligence analysis were technicians (in the sense that they were chosen because of language skills or codebreaking ability, rather than the ability to synthesize enemy intentions from fragments of information). The Navy in particular was groping towards an understanding of the difference between technical collection and analysis, and it was fortunate in having a few people who could do both (and particularly fortunate that two of them, Edwin Layton and Joseph Rochefort, were on the scene in Hawaii).

The Navy's short-term solution to this problem (which it had incompletely identified) was either to 1) reserve intelligence analysis in the hands of senior operational officers with other significant responsibilities (see also, Turner, Richmond Kelly) or 2) to try to replace those whose analytical work was not as good as their technical work with people the service though could provide better analysis (see also Safford, Lawrence).

It was not an easy process, and you can find its echoes in a lot of the post-hoc accounts of Pearl Harbor, and particularly the debate over the "Winds execute" allegations – which were probably far less significant than the question of just why the Japanese Consul's office in Honolulu had gridded a map of Pearl Harbor and was providing regular reports of ship positions.

IIRC the Japanese planned three raids. The third was to take out the POL facilities. They canceled the third because our defenses were too strong. Even the first wave of attackers was surprised at their warm reception.

Aircraft were parked wingtip-to-wingtip to guard them against expected sabotage, not an air attack or they would have been dispersed.

Weren't PBY search missions from the Aleutians going south canceled at the time the Japanese forces would have been passing through their search zone? If so why?

A PBY from my father-in-law's squadron VB-14 in Kaneohe Bay was armed and patrolling the mouth of Pearl Harbor looking for Jap subs along with a destroyer on the morning of Dec 7. They found one and sunk it. When did they start these patrols and why would they be doing them if no attack was expected?

There is a lot of evidence that we were to a large degree prepared for an attack at Pearl Harbor. I don't think it was feasible to run a 24-four CAP over the island without knowing the specifics of a forthcoming attack. There are different levels of preparedness. What level did Pearl Harbor have and who was responsible for planning it?

Wolfhag

The editors who took over the work of finishing Layton's manuscript after his death include an anecdote told to Roger Pineau (one of them) by a Japanese admiral, who stated that the prewar planning never even considered the importance of attacking the fuel facilities, because it was so focused on the tanks. Prange's book does state that Fuchida argued for a third attack on the fueling facilities, but that seems to have been an off-the-cuff rationale, and not a pre planned idea. Regardless, a strike o the fueling facilities would've severely limited the fleet's ability to operate in the Pacific, and given everything else that went wrong, we're fortunate the Japanese focused on the ships.

It's pretty clear that the "you are to consider this a war warning" message that went to commanders in the Pacific had generated some level of alert. The problem was its nonspecific nature: the information that was filtering through the system didn't necessarily indicate the outlines of the Japanese plan. The information that was known indicated 1) thatJapanese ships were in motion toward the Dutch East Indies, Malaya, and the Philippines, and 2) negotiations between the US and Japan were moving from deadlock toward rupture.

The million dollar question to everyone appeared to be "what are the Japanese about to do," which generated a lot of nonspecific alert measures. Japanese skill and ability were underrated, but the vulnerability of the British and the weakness of the Philippine garrisons were well known in DC, and matters of serious concern. Finally, the domestic political situation generated its own agonizing question: what happens if the Japanese attack the British and the Dutch, but not the US? There was still an enormous resistance in the US to entry into the war, but that had not prevented Roosevelt from giving the British some unofficial assurances about assistance of Japan attacked.

All of these problems – which looked huge on Dec 6- combined to distract everyone away from the few fragments of intercepted information that might have indicated an attack on Pearl Harbor. The Army and Navy took a lot of generalized precautions in the weeks before, but in the absence of intelligence indicators suggesting that an air raid on Pearl Harbor was coming, a lot went undone. But some of those generalized precautions mattered- I have seen it asserted that "90% of the sailors were onshore when the attack started," but I don't believe it- the casualty counts for "Arizona" and "Oklahoma" are too high for that to have been the case. Had the fleet had even twenty minutes warning, the ships would have been at quarters and closed up, which would've reduced their vulnerability tremendously. The real problem was an absence of the intellligence of enemy activity that would have been needed to cue the system to look in the right direction- and without that, a lot of people viewed the information they did get uncritically, and the raid succeeded.

Ships, not tanks!