Why was the Battle of Midway a turning point for the war in the Pacific theatre?

Answer 1

The simple fact that the US emerged as victor from the battle of Midway is not the reason for it being the turning point of the war in the Pacific.

The carriers Kaga, Akagi, Hiryū and Sōryū were lost by Japan while only managing to sink one American carrier, the Yorktown. The two large carriers that Japan had left after Midway, Zuikaku and Shōkaku were not enough to provide enough support for offensive action. Although Yamamoto still had a good number of surface ships including the battleships Yamato and Musashi, the largest and most powerfull ships deployed in WW2, he new he could accomplish nothing without air support and thus avoided conventional offensive after Midway.

More InformationJapan entered the war with a navy that in conventional terms was the equal of its US counterpart, and in naval aviation somewhat superior. The Japanese, who had just one ocean to worry about, could field huge battleships and numerous aircraft carriers to any location in the Pacific. They used four of their large carriers -- Hiryu, Soryu, Akagi, and Kaga -- at Pearl Harbor. At that time, the US Navy's Pacific Fleet possessed only three carriers; all three were at sea and not at Pearl on December 7.

Somehow, the paradox of attacking battleships with aircraft carriers was lost for a while, especially with the Japanese. Pearl Harbor was the first of a completely new type of naval battle, a type that would come to be measured by the numbers of aircraft and aircraft carriers applied to the fight. In spite of their masterful demonstration of this principle at Pearl Harbor, Japanese Naval planners continued to lust for that one big slugfest, the battleship-to-battleship exchange of high-explosive naval artillery that would permanently destroy the US Pacific Fleet. Until nearly the end of the war, Japanese strategists sought that "big battle." It never happened.

At Midway, thanks mostly to code-breakers and excellent planning, US forces ambushed a Japanese attack/invasion force that featured the same four aircraft carriers that had launched the attack on Pearl Harbor six months earlier. In the end, Hiryu, Soryu, Akaki, and Kaga were all sunk, with the loss of thousands of Japanese seamen and, most importantly, the loss of hundreds of Japanese aircraft and pilots. On the American side, the USS Yorktown was sunk.

Japan, a relatively small island nation with practically no domestic Natural Resources, was unable to recover from the losses at Midway. While the US was able to launch dozens of new aircraft carriers and support ships during the war years, Japanese ship production was unable to even maintain the 1941 navy.

Answer

To summarize some of the above, and place more emphasis where it belongs:

The Battle of Midway was a turning point NOT because of where it was fought, or even over possession of the area. That is, in real strategic terms, it was insignificant who actually owned Midway Island. While Japanese ownership of Midway would have been an annoyance to the US, the islands themselves were not of great strategy significance.

Rather, the important "turning point" result of the Battle of Midway revolves around the material losses that both sides sustained there.

Firstly, due to organization and industry, Japan was in a situation that it would not be easy to replace any losses it sustained in any fight. That is, while the IJN (Imperial Japanese Navy) was superior to any other country's at that point in time, Japan could generally only provide few replacements for any losses, and replacements (both in ships and men) would be inferior in quality to any lost.

The United States was in an opposite position - the US Navy was smaller, less experience, and had inferior equipment to the IJN. However, it could reasonably expect to receive better and more replacements than the IJN, and could look forward to having both superior numbers and superior quality in a year or so.

Thus, the goal of the IJN was to take advantage of their temporary superiority in numbers and quality, to inflict a crippling loss on the current USN, forcing the US into a strategic corner, from where its material and manpower advantage could be nullified. Destroying the USN at Midway would likely lead to the loss of the Hawaiian Islands to the IJN in the near future, before the USN's replacements could arrive in mid-1943. A Japanese occupation of Hawaii would effectively prevent ANY US assault from the mainland, and cut off Australia from aid.

In effect, the IJN's strategy was "kick them while they're down, so they stay down, since if they get back up, they're bigger than we are".

The USN, on the other hand, was essentially fighting a holding action, trying to do just enough to keep the IJN at bay, while they waited for the US shipbuilding industry to kick into high gear. The US Pacific strategy was effectively a single line item: Hold the Hawaiian Islands at any cost for their strategic value. If opportunity presents itself, nibble down the IJN's strength, but don't go looking for a fight.

To summarize the USN position: "Just Hold 'em off, reinforcements will be here next year."

The reason why Midway became a turning point was that the US came out of the battle in far better shape than a "rational" assessment would have them achieve, while the IJN came out in practically a "worst-case scenario" condition.

The IJN lost 50% of its Fleet Carriers (4 of 8), and about 30% of its experienced flight crews. Neither would have any replacements - they were gone for good. The US lost 25% of its current carrier force (1 of 4), and would receive bigger, better replacements in less than a year. In addition, the USN lost only about 5% of its flight crews, and they were quickly replaced (in less than a month).

This loss imbalance meant that even at the current (mid 1942) time frame, IJN had lost the ability to dominate the USN. Which meant, that Japan would only be able to conduct defensive operations - it did not have the strength to continue to operate offensively anymore. Indeed, the change in strategy is huge - post-Midway, the IJN staff spends all its time trying to figure out how to lure the US into a defensive trap (which is the only place now where the IJN can win), while the US now moves into pretty much solely an offensive mindset.
Midway took out the IJN's cream of the crop in airmen and flight-deck crewmen.
The US Navy was able to sink or heavily damage 4 Japanese carriers while losing only one of our own. Japan was unable to achieve air superiority after Midway. I think some admiral said "it wasn't the beginning of the end of the war but it was the end of the beginning".