This Day in WWII History (Intelligence Triumph Averts Disaster at Midway)

June 7, 1942—A story in the Chicago Tribune disclosed so many details of the recent Battle of Midway that it was impossible not to conclude that the U.S. Navy had achieved its victory by cracking the code of the Japanese Imperial Fleet. In the weeks following, the government of Franklin Roosevelt seriously considered trying Tribune publisher Robert McCormick and the paper’s sister publications, the New York Daily News and the Washington Times-Herald, for treason, only giving up the idea when it became apparent that prosecution might only draw attention to one of the great secrets of the war.

Miraculously, though suspicions were rampant among a number of Japanese officers, the high command never seems to have thought about changing its naval code, JN-25—a miracle almost as stunning to the American fleet as the victory that constituted the turning point in the Pacific War.

Only part of the story of this engagement is told by the lopsided comparison in losses: for the Americans, 1 aircraft carrier, 1 destroyer, 151 aircraft, 307 dead; for the Japanese, 4 aircraft carriers, 225 aircraft, 3,000 dead. Just as important, the Japanese juggernaut that had appeared invincible after Pearl Harbor had been checked. Three years of hard fighting remained, but from here on Japan would be on the defensive rather than the offensive.

In a sense, Midway can be regarded as the reverse of Pearl Harbor, the most massive intelligence failure in American history. By March 1942, the Navy’s Combat Intelligence Office, nicknamed “Hypo,” had managed, through analysis of decrypted messages and radio traffic between Japanese vessels and planes, to estimate within 300-400 miles the location of most Japanese ships. American codebreakers were working without the computers that modern cryptoanalysts have, without decoding machines, without even a Japanese code book—and yet, before long, they had managed to crack one out of every five groups of messages.

Soon, the codebreakers had figured out another Japanese secret: an impending attack on the Midway atoll in the Central Pacific. The Commander in Chief of the Japanese Combined Fleet, Admiral Isoruku Yamamoto, wanted to finish the job he had started at Pearl Harbor and wipe out the remainder of the American fleet. He would take Midway and, when the Americans came out to defend this outpost before Hawaii, he would turn around with his giant force—at that point, the largest ever to sail—and destroy a fleet that, even after the devastating surprise attack six months before, remained dangerous.

The codebreakers were fortunate to be backed by Admiral Chester W. Nimitz, who had succeeded Husband Kimmel as commander of the Pacific Fleet after the Pearl Harbor debacle. Skeptics—including a number on the staff of Admiral Ernest King, commander-in-chief of the U.S. Fleet—wondered if the Japanese were really executing a feint. But Nimitz not only strongly supported the intelligence analysts’ conclusions, but he began immediately to execute a plan based on them.

Crucial to Nimitz’s plan was the Yorktown, an aircraft carrier badly damaged at the Battle of the Coral Sea on May 7. The Hypo team estimated that American planes would first make contact at Midway with Japan’s at 0600 hours on June 4. The American fleet badly lagged Japan in surface warships (28 versus 88), and though surprise would help, as many aircraft carriers had to be summoned as possible to even the odds. A complete repair for the Yorktown, under these conditions, was out of the question; the Americans would have to get her just ready enough to fight.

Supporting the codebreakers demonstrated in one way Nimitz’ quiet, effective handling of men; the appointment of Admiral Raymond Spruance to take the place of William F. Halsey, one of the American fleet’s foremost aircraft-carrier commanders (sidelined by a painful skin disease), was another. Many feared that the aggressive Halsey (his slogan: “Kill Japs, Kill Japs, Kill more Japs!") would be irreplaceable, especially since Spruance was a battleship admiral.

Little did they know that Spruance, for all his modesty, could strike every bit as effectively as Halsey—and that he would, in a key moment, also show a necessary care that—notably, at the Battle of Leyte Gulf—would elude “Bull” Halsey.

For once, Yamamoto’s strategic skills failed him, a symptom of what Japanese officers years later would recall as symptomatic of a larger condition afflicting their forces: "victory disease," or overconfidence. He had used a resignation threat to override the qualms of Japan’s Naval General Staff about the wisdom of the Midway campaign, then, to mollify them, agreed to a simultaneous strike against the Aleutians far north. The result was that, instead of a concentrated force, his ships would be scattered across thousands of miles, with many not around in case he needed them. The fleet would be pointlessly, hopelessly overextended.

At the same time, Nimitz’s plans called for falling on the flank of the Japanese Combined Fleet before it knew what hit them. The strike depended on timing and, as it turned out, more than a bit of good luck.

The commander who implemented the plan that worked because of this confluence of timing and luck was Spruance.  Though, unlike Halsey, he was a battleship rather than carrier specialist, he exploited his carriers to their greatest potential now. Spruance guessed—correctly—that the Japanese would launch not one, but two attacks against Midway—and that he could catch them as they were readying the second strike. At 0700 on June 4, then, on Spruance’s orders, two American carriers, the Hornet and Enterprise, launched their planes, while the Yorktown followed suit some 90 minutes later.

Not all the Americans’ plans worked—the Japanese had no problem fending off slow-moving torpedo bombers—but even this worked to the advantage of Nimitz and Spruance. While the Japanese were preoccupied with the torpedoes, they did not notice until too late that dive bombers from the American carriers were honing in on the huge red circles on the yellow Japanese decks that their attackers called “meatballs.” The American pilots found their marks and fired, at the exact moment when their targets had fuel lines and bombs strewn over their decks. Within six minutes, three carriers—Akagi, Kaga, and Soryu—had been struck and turned into fireballs. All would eventually sink.

Nor was misfortune at an end for the Japanese. After a noontime hit on Yorktown by Hiryu, Spruance ordered 24 dive bombers and torpedo planes to go, without fighter escort (they were still needed to protect Midway), to find Japanese Vice Admiral Chuichi Nagumo’s fourth and last carrier. Again, time and luck were with the Americans; they sighted and bombed their target just as Hiryu’s crew was sitting down to dinner. Hiryu soon also sank.

After the battle, some critics complained that Spruance should have pursued Yamamoto further. But Miracle at Midway, by Gordon W. Prange, Donald Goldstein and Katherine Dillon, correctly pointed out that this would have exceeded the American admiral’s instructions from Nimitz—i.e., defend Midway—and would have risked a dangerous nighttime action in which he would have been outnumbered in destroyers and battleships.

By an interesting conjunction of events, the Yorktown sank within 24 hours of the Tribune’s report of the intelligence coup at Midway. The carrier and its brave crew would not have been positioned to help tilt the balance at the battle without that intelligence. Had they known and revealed all their information sooner, the Tribune and its isolationist Republican publisher, McCormick, would have put at risk the American key to victory. As it was, they endangered subsequent operations in the Pacific.

The Battle of Midway was a major morale-booster for an American military still reeling from Pearl Harbor, as well as the civilians who dreaded what would happen to family members in harm’s way. Conversely, as the first decisive defeat for the Japanese naval fleet in three centuries, it also punctured the aura of invincibility possessed by Yamamoto and his men.

Finally, as noted in Gerhard Weinberg’s A World at Arms: A Global History of World War II, the victory “made it possible for the United States to maintain in principle and eventually in practice a strategy that placed first emphasis on victory over Germany.”

Ironically, the key intelligence officer at Hypo who had made the victory possible did not receive recognition for his great work until after his death. Though Nimitz had warmly recommended Commander Joseph Rochefort to Admiral King for a decoration for his intelligence work, the recommendation was not only rejected, but Rochefort was removed from his duties with Nimitz. It wasn’t until 1986, nine years after he had died, that his children received from Ronald Reagan the President’s National Defense Service Award, the highest military award during peacetime, for the work leading up to Midway.

(The photo shows the Japanese aircraft carrier Akagi and a destroyer maneuvering below thin clouds while under high-level bombing attack by USAAF B-17 bombers, shortly after 8 AM, June 4, 1942.)