Why did Yamamoto reprimand Nagumo after Pearl Harbor?

Question

I am reading the book "Shattered Sword" and it states that Yamamoto "rebuked" Nagumo after Pearl Harbor. I thought Pearl Harbor was considered a great success? Anyone know why Yamamoto thought it necessary to reprimand Nagumo? TIA

Answer 1

Essentially for failing to carry out a third attack. Wikipedia (my emboldening):

In the end, five American battleships were sunk, three were damaged, and eleven other cruisers, destroyers, and auxiliaries were sunk or seriously damaged. The Japanese lost only 29 aircraft, while 74 were damaged by anti-aircraft fire from the ground. The damaged aircraft were disproportionately dive and torpedo bombers, seriously impacting available firepower to exploit the first two waves' success, so the commander of the First Air Fleet, Naval Vice Admiral Chuichi Nagumo, withdrew. Yamamoto later lamented Nagumo's failure to seize the initiative to seek out and destroy the US carriers, absent from the harbor, or further bombard various strategically important facilities on Oahu. Nagumo had absolutely no idea where the American carriers might be, and remaining on station while his forces cast about looking for them ran the risk of his own forces being found first and attacked while his aircraft were absent searching. In any case, insufficient daylight remained after recovering the aircraft from the first two waves for the carriers to launch and recover a third before dark, and Nagumo's escorting destroyers lacked the fuel capacity for him to loiter long. Much has been made of Yamamoto's hindsight, but, in keeping with Japanese military tradition not to criticize the commander on the spot, he did not punish Nagumo for his withdrawal.

which suggests the criticism may have been somewhat unjust.

The "strategically important facilities" included fuel stocks:

Wikipedia:

he was later criticized for his failure to launch a third attack, which might have destroyed the fuel oil storage and repair facilities. This could have rendered the most important U.S. naval base in the Pacific useless, especially as the use of the submarine base and intelligence station at the installation were critical factors in Japan's defeat.

Answer 2

Because Yamamoto was one of the few admirals in the Japanese fleet that understood the importance of logistics. Other Japanese admirals, such as Nagumo, measured their success by the damage to enemy warships.

Specifically, Nagumo was satisfied with his two strikes, which blew apart the battleship USS Arizona, and severely damaged all but one of the other seven American battleships. That put the U.S. Pacific Fleet out of action for some time.

But Yamamoto wanted Nagumo to make a third strike to destroy the fuel supplies and dock facilities. That would have done more damage to the American Pacific effort than the loss of its warships.

Yamamoto also reproached Admiral Mikawa, who won a victory at Savo Island, for the same mistake. Mikawa sank several allied cruisers with a midnight surprise attack, and then left the scene. But Yamamoto faulted Mikawa for not destroying the Allied transports, with their supplies and reinforcements.

Yamamoto understood better than other Japanese admirals that the whole purpose of defeating enemy warships was to earn the right to destroy their "soft" targets. The other admirals felt that sinking enemy ships was "enough."

Answer 3

Because Nagumo's execution of the attack while a tactical victory, was a strategic missed opportunity. It did minimal damage to the primary strategic targets.

Pearl Harbor resurrection: the warships that rose to fight again
The target ship USS Utah, and the battleships USS Arizona and Oklahoma, were the only ships the Japanese left beyond repair.

Yamamoto planned Pearl Harbor, while Nagumo commanded the attack. Yamamoto criticized Nagumo's execution of the attack because it failed on three of Yamamoto's greatest strategic targets. Nagumo was too conservative and overly concerned with taking out Battleships rather than more important targets from Yamamoto's perspective.

1. Naguma's attack failed to destroy the 4.5 million gallons of fuel reserves both for ships and aircraft at Pearl Harbor. If those tanks had been destroyed it would have required the US Pacific Fleet to abandon Pearl Harbor as a forward base and required it to fall back on San Diego. It would have taken years for the US to rebuild those forward reserves and conducting the Pacific war from San Diego also would have greatly impacted the effectiveness US Navy's operations.
2. Naguma's failure to destroy the US Aircraft Carriers which meant the United States still had offensive capabilities which would come back to haunt Japan at the Battles of Coral Sea and most especially Midway.
3. The Pearl Harbor ship yards which would go on to return most of the ships sunk in pearl harbor to service within 3 months were not destroyed.

Harbor resurrection: the warships that rose to fight again
Within three months most of the smaller ships and three of the battleships – the USS Pennsylvania, the USS Maryland, and the USS Tennessee – were either returned to service or refloated and steamed to the continental US for final repairs.

Answer 4

The Japanese Navy was structured differently than the US Navy in that the Admiral who was in overall command didn't have the freedom to select who was the operational commander of the task force. The operational commander was selected based on seniority. To select someone else would have been considered a loss of face and that would have been a serious rebuke of the person who was passed over.

Both Yamamato and Nagumo opposed declaring war on the US. It was traditional for the overall commander to have one of his staff design the operation as if that officer was in command. Yamamoto selected one of his staff, a Commander Genda, to make up his plan. After the end of WW 2, Commander Genda was interviewed in 1947 and again about 25 years later on the plan he designed. Commander Genda gave a detailed explanation of his plan. This plan was much more aggressive than Admiral Nagumo's plan.

Genda's plan involved two separate forces. One was the carrier task force of six carriers and escort ships. The second force consisted of battleships and support ships along with at least 11 transport ships holding 30,000 troops. The two would sail independently, and when the carrier group arrived at the launching position, the invasion force would be located about 200 miles south of the entrance of Pearl Harbor. When the second air raid on Pearl Harbor returned to their carriers, the invasion task force would move closer to Pearl Harbor and be joined by the carrier task force.

Then the invasion of Oahu would begin. The shelling of southern Oahu would commence as the invasion troops would move into place and prepare to land on the beaches, supported by the aircraft from the six carriers and the guns of the battleships and other escorting warships.

The theory behind this was to use Oahu as a bargaining chip. The negotiations would have allowed the exchange of Oahu for the US granting Japan free access to the South China Sea and the ports in southeastern Asia. This would have included a lifting of the oil embargo as well as all other embargos on Japan. This would have held off invading the Philippines, as those troops would have been used at Oahu instead.

Admiral Nagumo rejected this plan as being too risky. His orders were to neutralize the US Navy Pacific fleet, which he felt was accomplished. With the absence of the carriers at Pearl Harbor, Nagumo was concerned the carrier task force was going to attack his carrier force, so he exited the area and headed toward Midway where he would launch air attacks on Midway. It would have reprinted a loss of face on Admiral Nagumo.

A version of Genda's plan was used in the Midway Campaign six months later.

It appears Admiral Nagumo was focused on tactical results instead of the strategic goals of the reasons for attacking Pearl Harbor in the first place.

As history showed us, the US Navy's strategy of using a combined force of carriers, battleships, and other supporting warships all supporting the invasion forces would prove to be the best type of attack to use against an enemy-held island.

Answer 5

If Yamamoto understood the oil storage facility was more important than sinking the battleships, he should have made that clear to Nagumo.

Knowing the critical importance of success on that opening day, Yamamoto should have been with the attacking fleet.

Yamamoto's priority list going into the battle should have been this:

1. destroy the carriers
2. destroy the oil storage tanks

And since he should have calculated the possibility that the carriers were out of port, he HAD to make sure Nagumo knew the tanks were high priority. So those oil tanks should have been hit on the first wave, certainly the second. If Yamamoto had been there when the first wave returned, he could have made sure the tanks became the priority, since by then they would know the carriers were not present.

I think because of Yamamoto's famous remark about waking a sleeping giant we tend to falsely believe he was not eager for the fight. I think it's more the case that he was eager for it, but had moments of doubt. But the mistakes are his more than anyone's, since he was responsible for the strategy of trying to completely neutralize the American threat in a way that gave the Japanese a free run for at least a year. Yamamoto could not foresee that the US would quickly raise most of the ships, but he certainly understood the vital importance of either getting the carriers or getting the oil facility.

Answer 6

The attack on Pearl Harbor was a huge gamble. Nagumo had just won big and wanted to take his winnings home. I think that was noted by Clausewitz as a natural tendency for winners in any battle.

Yamamoto was a gambler who understood what a longshot it was for Japan to defeat the United States. The point of Pearl Harbor was to knock the US out. He would have rolled the dice again, recognizing that with its carriers and port facilities intact the US was down, but not out. Without Hawaii as a base, the US may have been knocked out. At least that was the point of the bet.

Answer 7

Yamamoto and Nagumo are 2 very different officers. Yamamoto is someone who is flexible and see things 2-3 steps ahead whereas Nagumo is someone who follows the doctrine and mission objective to the letter. He isn't someone who can be left alone to take the initiative or to further an advantage gained.

Answer 8

The US could have quickly restored any oil facilities Nagumo might have destroyed since its oil resources were colossal. Remember that one of the main reasons for the Pearl Harbor attack was FDR's imposition of oil sanctions that hamstrung Japan's economy. The 1941 attack[s] on Pearl Harbor and the East Indies TEMPORARILY eliminated the USA's (and the British Empire's) ability to interfere with Japan's compensatory seizure of the oil resources of southeast Asia.