The United States had been at war with Japan for about 18 months in April of 1943. After the disastrous events at Pearl Harbor, and the resultant Japanese victories in the Philippines, the U.S. was rocked on its heels. But six months after the defeat at Pearl Harbor, the Japanese suffered a catastrophic defeat at the Battle of Midway. The Imperial Navy had lost four of its frontline aircraft carriers and all of their experienced pilots. Unknown to them, the defeat was because the U.S. had broken their secret JN-25 codes. That would later cost them their best admiral and the architect for the Pearl Harbor mission.

Admiral Isoroku Yamamoto was the commander of the Japanese Imperial Navy. He had spent time in the United States and traveled extensively when he attended Harvard. While stationed in Washington as a Naval Attache, he developed an affinity for poker as well for America in general. Yamamoto was against the alliance between Japan and Germany and was against war with the Americans.

Admiral Isoroku Yamamoto

He knew that in a long, protracted war, America’s vast natural resources and their industrial might would crush Japan. So when the Japanese leaders insisted on war, he planned the attack on Pearl Harbor, hoping for a quick knockout of America’s fleet followed by a quick peace accord.

Japanese propaganda attributed a quote supposedly by Yamamoto that he never said but was believed by the Americans that “he hoped to dictate peace terms while sitting in the White House.” So when the Americans intercepted a radio message that Yamamoto was going to inspect forward Japanese troops they quickly decided to act.

Yamamoto would be flying from Rabaul to Balalae Airfield, on an island near Bougainville in the Solomon Islands, on April 18. He and his staff would be flying in two medium bombers (Mitsubishi G4M Bettys of the Kōkūtai 705), escorted by six navy fighters (Mitsubishi A6M Zero fighters of the Kōkūtai 204), to depart Rabaul at 06:00 and arrive at Balalae at 08:00, Tokyo time.

The last image of Yamamoto alive, moments before he took off on his last flight from Rabaul.

The Americans stationed at Guadalcanal had to fly about 1000 miles round trip to intercept Yamamoto and his flight. It was well beyond the range of the F4F Wildcat and F4U Corsair fighters assigned to the Navy and Marine Corps units on the island. It was turned over to the Army pilots of the 339th Fighter Squadron, 347th Fighter Group, whose P-38G Lightning, equipped with drop tanks, had the necessary range to intercept and engage the Japanese over Bougainville.

The twin-engined Lightning had a 20mm cannon and four .50 caliber machine guns in the nose. Equipped with a 330-gallon drop tank, the aircraft would have enough fuel to fly to the area, engage the Japanese and return safely. 18 Lightnings were tasked with the mission, one flight of four whose mission was to kill the two Betty bombers and the rest to fly cover to protect them from Japanese Zero fighters. The mission pilots were:

The USS Ward Fired the First US Shots of WWII at Pearl Harbor

Read Next: The USS Ward Fired the First US Shots of WWII at Pearl Harbor

American pilots Thomas G. Lanphier Jr., Besby F. Holmes, and Rex T. Barber

Capt. Thomas G. Lanphier, Jr.
Lt. Rex T. Barber
Lt. Jim McLanahan (dropped out with a flat tire)
Lt. Joe Moore (dropped out with faulty fuel feed)

The cover flight consisted of:
Maj. John Mitchell
Lt. William Smith
Lt. Gordon Whittiker
Lt. Roger Ames
Capt. Louis Kittel
Lt. Lawrence Graebner
Lt. Doug Canning
Lt. Delton Goerke
Lt. Julius Jacobson
Lt. Eldon Stratton

The Americans took off at 0725 and had to fly a roundabout route there to confuse Japanese radar. The plan was to arrive precisely when Yamamoto’s flight arrived at 0935. In a remarkable feat of dead reckoning, the Americans arrived at 0934, a minute early. They spotted the Betty bombers, just as they dropped down into view in a light haze. The P-38s jettisoned their drop tanks and began to climb to intercept the bombers while paralleling their position.

As Mitchell turned to attack the escort fighters, Barber dove on the fleeing bombers. With a quick devastating burst, he fired into the right engine and fuselage. Turning, he then hit the left engine. The Betty began trailing heavy black smoke and rolled violently and pitched and crashed into the jungle. Yamamoto was dead. But Barber didn’t know which plane he was in and quickly engage the second Betty.

He fired on the right engine of the Betty, which quickly emitted a white vapor. Barber pressed home the attack and the Betty crashed into the ocean. He didn’t realize it, but that plane carried Vice Admiral Matome Ugaki, part of Yamamoto’s staff. He and the crew survived and were rescued by the Japanese Navy later.

Desperately short on fuel, the Americans, after a brief skirmish with the Zeros, broke off for home. They landed with nearly dry tanks. Lanphier did a victory roll over the tower and broke security protocol by announcing on the radio, “That son of a bitch will not be dictating any peace terms in the White House” He claimed credit for shooting down Yamamoto’s aircraft. His account was disputed by the other American pilots as well as surviving Japanese pilots after the war.

The Japanese launched a rescue party for Admiral Yamamoto and he was found the next day. He was thrown clear of the wreckage, still strapped in his seat, grasping his katana sword. He suffered two bullet wounds, one in the shoulder and the other under his lower left jaw that exited above his right eye. That killed him instantly.

The Japanese public wasn’t told about his death until May 21, 1943. The U.S. released a cover story to hide that the Americans were reading Japanese code, that civilian coastwatchers in the Solomons observed Yamamoto boarding a bomber and relayed the information by radio to American naval forces in the immediate area.The Japanese never thought their codes had been broken.

Donald A. Davis, who wrote the book, “Lightning Strike” about the Yamamoto mission—suggests the reason was arrogance. He said that “in the arrogant and incredibly naïve Japanese belief that Western minds could not possibly understand the intricacies of their complex language, particularly when it was wrapped in dense codes. Despite all of the clues, hubris had overtaken them, and they were unwilling to accept the logical truth that their code was worthless.”

Five minutes at the Battle of Midway turned the tide

Read Next: Five minutes at the Battle of Midway turned the tide

The Yamamoto quote that Japanese propaganda so misused was later found in a letter that the Admiral wrote to a friend. He said that he knew the United States would fight long and hard and would be a formidable foe.

It is not enough that we should take Guam and the Philippines or even Hawaii and San Francisco. We would have to march into Washington and sign the treaty in the White House.

But the propagandists in the military turned it into a self-serving lie after the victory at Pearl Harbor. They changed his quote to read: I shall not be content merely to capture Guam and the Philippines and occupy Hawaii and San Francisco. I am looking forward to dictating peace to the United States in the White House at Washington.

America and the military bought it completely and that fact put a huge target on his back. Those same propagandists ultimately cost Yamamoto his life. Would the U.S. risk losing the advantage of the Japanese codes if sentiment wasn’t as high against him? It is debatable. But judging by the glee from the front lines all the way to the White House, they may not have risked it.

Photos: National Archives