Except the Lt. Col. needed to do a bit more research. While the Ultra secret wasn't revealed in the press, the fact that we were reading Jappanese codes in the summer of 1942 WAS revealed by the Chicago Tribune and by a Congressman during a speech on the House floor.
WORLD WAR II MAGIC:
The Chicago Tribune, Midway, and MAGIC
The American success in the Battle of Midway (3-6 June 1942), the turning point in the naval war in the Pacific, is attributable in large part to the U.S. Navy's advance knowledge of Japanese plans. That knowledge came from communications intercepts and cryptanalysis (MAGIC). Soon after the Battle of Midway, the Chicago Tribune reported that U.S. naval intelligence knew the Japanese navy's plans, strength, and dispositions prior to the battle. As Holmes put it in Double-Edged Secrets, "[a]ny informed reader could only conclude that Japanese codes has been broken." (p. 107) The compromise of the security around MAGIC and the failed effort to hold the newspaper and journalist Stanley Johnson accountable is the focus of the material included here.
Check out the links on this article -- they list some papers that discuss whether the reporters and editors committed treason.