The Battle of Midway is widely regarded as the moment the United States seized the strategic initiative in the Pacific, dealing a devastating blow to the Imperial Japanese Navy. What is less frequently discussed is that the battle also exposed a significant intelligence and security failure during World War II—one that might have produced far more damaging results had a series of fortunate mistakes not altered the outcome.
Although the engagement ultimately ended in a major American victory, the events surrounding it revealed vulnerabilities in wartime security that, under different circumstances, could have had serious consequences for the Allied war effort.
Battle of the Coral Sea
The story begins with the Battle of the Coral Sea in May 1942, a month before the Battle of Midway. Australian-American reporter Stanley Johnston, writing for the Chicago Tribune newspaper, was aboard the USS Lexington (CV-2). Having been vetted by the Federal Bureau of Investigation (FBI), he was the only journalist aboard the American aircraft carrier.
During the engagement, Lexington was sunk by the Japanese. While evacuations were underway, Johnston ran below deck to rescue sailors who’d been badly burned and helped transfer them onto the USS Barnett (APA-5). From there, he and the other survivors began their voyage to San Diego, California, via Nouméa.
Stanley Johnston became privy to top-secret information
While aboard the USS Barnett, Stanley Johnston roomed with Cmdr. Morton T. Seligman, executive officer of the sunken USS Lexington. Seligman was privy to US Navy intel and received a top-secret message from Adm. Chester Nimitz, no. 311221.
While it’s unknown whether he told Johnston or if the reporter happened upon the note, its contents were soon published for all of the United States to read.
Johnston published 15 first-hand accounts from the Battle of the Coral Sea in the Chicago Tribune. He also wrote up a story on the American victory at Midway, with the title, “Navy Had Word of [Japanese] Plan to Strike at Sea.” It was a story so big that it was picked up by the San Francisco Chronicle and published on its front page.
Implied, but not explicitly stated
Although the article stopped short of explicitly stating that the U.S. Navy had broken the Japanese code, it strongly implied as much by explaining that American officials had advance knowledge of the planned attack on Midway, including the size of the enemy force and the timing of its operation.
The article’s publication triggered widespread anger within both the Navy and the federal government. President Franklin D. Roosevelt was especially upset with the reporter, who was aware that stories involving sensitive military matters were expected to be cleared by Washington before publication. While many suspected that Navy personnel had been careless in handling classified information, wartime policy required all dispatches from combat areas to undergo review by the Naval Censorship Office before they could be released.
Stanley Johnston was put before a grand jury
Due to the perceived severity of the security breach, the FBI, the U.S. Navy, and the Department of Justice jointly urged U.S. Attorney General Francis Biddle to pursue charges against journalist Stanley Johnston and Chicago Tribune managing editor Patrick Maloney under the Espionage Act of 1917. If brought forward, it would have marked the first and only time that law was applied against members of the press.
The early phase of proceedings included four days of witness testimony, with a fifth day scheduled to feature senior Navy officials. Their intended role was to explain to the jury how Johnston’s reporting could have jeopardized ongoing wartime operations. However, Navy leadership, including Admiral Ernest J. King, ultimately refused to allow officers to testify. This decision significantly weakened the prosecution’s case, as the grand jury struggled to evaluate charges that were not clearly supported by direct military explanation.
In the end, Johnston and Maloney were acquitted due to insufficient testimony and because the Espionage Act didn’t cover enemy secrets. The outcome also helped prevent the issue from receiving prolonged public attention, reducing the likelihood that enemy forces would further exploit awareness of the incident.
Aftermath of Stanley Johnston’s actions
As the grand jury inquiry continued, government officials considered several additional actions that might be taken against the Chicago Tribune. Among the ideas discussed were directing the U.S. Navy to seize ships transporting newsprint across the Great Lakes or restricting deliveries of pulp to the newspaper’s owner, Robert R. McCormick. Ultimately, neither measure was implemented.
For the Navy, a major concern never materialized: Japan did not learn that its communications had been compromised. Although Japanese authorities periodically modified their encryption procedures, the changes failed to eliminate key weaknesses, and the principal naval code, JN-25, continued to be susceptible to Allied codebreaking efforts.
Morton T. Seligman faced serious professional consequences for his role in the information leak. Ernest King reassigned him away from sea duty and prevented his advancement to the rank of captain. The setback permanently damaged Seligman’s career and eventually resulted in his compulsory retirement from the Navy in 1944.