Battle of Midway: American Intelligence, SBDs — and Luck — Made the Difference

U.S. forces defeated a major attack by the Japanese Imperial Navy in the historic June 4-7, 1942, Battle of Midway, even though the Japanese fleet seemed to have every advantage.

As docent John Lynch said in a presentation at the Museum on the 79th anniversary of the great sea battle, the U.S. was outclassed in the size of its forces and the combat experience of its aircrews. But the U.S. Navy had a great advantage in intelligence that changed the odds and led to the sinking of all four of the attacking Japanese carriers. The U.S., which also had a large dose of good luck, lost one carrier.

                The victory changed the course of the Pacific war, and is included in the ranks of such other famous battles as Gettysburg and Trafalgar.

                “Midway thrust the [Japanese] warlords back on their heels, caused their ambitious plans…to be canceled, and forced on them an unexpected, unwelcome, defensive role,” said Samuel Elliot Morison, the U.S. Navy’s official historian of World War II.

                The Americans “had no right to win. Yet they did, and in doing so they changed the course of a war”, Walter Lord writes in “Incredible Victory.”

                But it was far from clear at the time that an American win at Midway would change the course of the Pacific war. The only certainty was that much hard fighting lay ahead, Lynch said at the session, which included the public flight of the Museum’s rare Douglas SBD Dauntless. The type played a major role in the battle.

                Japanese forces had been on a rampage since the attack on Pearl Harbor six months earlier, and had a bold plan to trap and destroy what remained of the American Pacific fleet at Midway. Tokyo would then demand a peace that would allow it to freely control its vast new territory.

                American naval commanders had been doing what President Franklin D. Roosevelt and Adm. Ernest J. King, Commander of the U.S. Fleet and Chief of Naval Operations, wanted them to do — being careful not to lose any precious aircraft carriers. It was clear that it would take many months to build new ones.

                The U.S. Navy did score a victory over the Imperial Japanese Navy in the Battle of the Coral Sea, May 4-8, 1942, the first sea battle in which ships never saw each other. Ships under Adm. Chester W. Nimitz, commander-in-chief of the U.S. Pacific Fleet, negated a Japanese plan to mount a sea-borne invasion of Port Moresby, New Guinea. It was the first time Japan had failed in a major operation, and a strategic victory for the U.S.

                But, while Nimitz’s planes sank a light Japanese carrier and a cruiser, and severely damaged the large Japanese carrier Shokaku, he lost one carrier, the USS Lexington, and left the battle with a crippled one, the USS Yorktown.

                Nimitz’s counterpart, Adm. Isoroku Yamamoto, commander-in-chief of the Imperial Japanese Navy’s Combined Fleet, thought he had destroyed two American carriers.

And he didn’t rush to repair Shokaku, sending it back to Japan, where the job would be done in two or three months.

But Nimitz made it a top priority to repair Yorktown quickly. The battered ship arrived at Pearl Harbor amid estimates that it would take months to get it back in action, but it sailed just 72 hours later.

                Nimitz’s pressure to get the job done in record time was driven by his receipt of brand-new intelligence that Japan was planning a big operation. The quality of that intelligence was so good that he felt he could set aside the rules of Roosevelt and King, Lynch said in a telephone interview before his June 5 presentation at the Museum. Lynch said code-breakers weren’t reading all Japanese messages. But they had become much better at their craft, particularly after the Doolittle raid of April 18, 1942.

                That raid, in which B-25 medium bombers of Lt. Col. Jimmy Doolittle took off from the USS Hornet and struck Japanese targets, prompted Japan to flush elements of its armed forces to counter any additional American attacks. But that required the transmission of many messages, and American code-breakers were listening. And the more they listened, the more they learned.

                Working overtime for what must have seemed like endless hours and using all aspects of signals intelligence, they discovered that the Japanese were readying for a major operation at a place the Japanese were calling “AF.” The code-breakers assumed it was Midway, but couldn’t confirm it.

So, in a classic bit of trickery, the U.S. Navy on Midway sent a message of its own, in the clear, to American forces, saying Midway was short of fresh water. A Japanese message to Japanese forces shortly thereafter saying “AF” needed water confirmed the Midway suspicion.

Word was passed immediately to Nimitz, who sent Yorktown, Hornet and Enterprise to Midway, ready for a fight.

                Nimitz knew “who was coming, the number of ships, where they were coming from, and when they were going to be there,” Lynch said in the interview. A U.S. Navy PBY Catalina patrol plane, like the one in the Museum, sighted the enemy ships. Nimitz got the message and the fight was on.

                Yamamoto had no idea that Japanese transmissions were being more and more clearly understood by American code-breakers, and didn’t know that Nimitz’s carriers were lying in wait. He assumed that his four carriers — Akagi, Kaga, Soryu and Hiryu — would win the final battle for Japanese supremacy.

                But Yamamoto also knew that his time was limited. The attack on Pearl Harbor, which he planned, had awakened “a sleeping giant and [filled] him with a terrible resolve,” he reportedly wrote in his diary. He also is said to have written that “In the first six to twelve months of a war with the United States and Great Britain, I will run wild and win victory upon victory. But then, if the war continues after that, I have no expectation of success”.

                A victory at Midway was vital to Japan. But Yamamoto lost not only all his carriers and many of his most experienced airmen, but a heavy cruiser, 248 aircraft and over 3,000 men as well. It was an epic defeat.

                American losses also were steep — Yorktown was eventually sunk by a Japanese submarine after being devastated in an air attack; the destroyer USS Hammann was lost; 150 aircraft were destroyed, and 305 men were killed.

But the dive-bombing role played by SBD Dauntlesses like the Museum’s was central, leading directly to the American win. Four squadrons of Navy SBDs attacked and sank Soryu and Kaga on June 4, and Akagi and Hiryu on June 5. They also damaged two heavy cruisers, with one, Mikuma, finally sinking.

But luck was on the American side. For one thing, SBDs, which dove from high altitude to drop their bombs, happened to find Japanese carriers just as the carriers’ attention was drawn to TBD Devastator torpedo bombers attacking them from low altitude.  Thirty-five of forty-one TBDs were lost. None of their torpedoes hit.

Eighteen of the forty-seven attacking SBDs never made it back to their carriers.

                “The role of the Dauntless was huge, and for us as a museum to have one in our collection is very important,” Lynch said in the interview.