The USS Indianapolis, too large to enter the harbor at Tinian, anchored about one-half mile offshore to unload about one-half the uranium for the Little Boy bomb.
Little Boy exploded almost 2,000 feet above Hiroshima on August 6, 1045.
The following are the author’s remarks delivered at the Peace Park in San Jose, Tinian, Aug. 7, 2023.
SEVENTY-EIGHT years ago, the Pacific War was still undecided, even though the Japanese Army was falling back on all fronts while the U.S. Navy and the U.S. Army Air Forces were imposing their will on the Imperial Japanese Navy.
By this date in August 1945, the Chinese army had broken in to Kweilin, while other Chinese units captured Tanchuk Airfield. Elements of the Australian 7th Division were working their way through Borneo. The U.S. Tenth Air Force was fighting at Kunming. The X Corps was fighting in Mindanao. Units of the British Fleet had joined the U.S. Third Fleet warships in bombarding Japan’s ports and shoreline facilities. The U.S. Eighth Army landed on Balut Island at the entrance to Sargini Bay, the Philippines. And, MacArthur was preparing for the invasion of Kyushu, Japan, Operation Olympic, scheduled for November 1,1945. Airbases could be established there in support of forward operations on Honshu and the march to Tokyo, what was left of it. An estimated 10,000 people were dying daily throughout the Indo-Pacific.
Demonstrating America’s industrial might, the combined Allied naval armada preparing for the invasion of Kyushu Island, Japan, included 42 aircraft carriers, 24 battleships, and 400 destroyers. Fourteen U.S. divisions, some 280,000 men, were scheduled to take part in the initial landings.
The Japanese defense relied heavily more than 10,000 aircraft, including Kamikaze’s, as well as hundreds of newly built suicide boats to attack Allied ships offshore.
Admiral King, Commander-in-Chief of the U.S Navy, was so concerned about losses from kamikaze attacks that he and other senior naval officers argued for canceling the operation.
Fat Man, even more powerful than Little Boy, was the last atomic bomb ever used in combat.
The Battle of Okinawa had cost the U.S. 49,151 casualties. Of those, 12,520 were killed or missing and 36,631 were wounded in action. If the U.S. casualty rate during the invasion of Japan had been only 5% as high per unit area as it was at Okinawa, the U.S. would still lose an estimated 297,000 soldiers (killed or missing) by the end of Operation Downfall.
At this time, the best guesses on the end of the war was mid-1946, although some chanted “The Golden Gate in ’48.”
Manhattan Project
Unknown to the outside world, the U.S. had been developing an atomic bomb, a tool they hoped would bring the war to a sudden and decisive end.
On January 19, 1945, Dr. J. Robert Oppenheimer, Director of the Los Alamos Laboratory, sent General Leslie Groves, Commander, Manhattan Project, his first prospective timeline for bomb deliveries: August 1 for one Little Boy and one Fat Man. That information sparked the decision on where the bombs would be assembled for delivery to Japan.
Over 1,000 planes, B-29s and fighter aircraft from Iwo Jima and Okinawa, flew over the USS Missouri on September 2, 1945, as the ceremony ending World War II in the Pacific ended.
General Groves dispatched Commander Dick Ashworth to Guam on February 10 to inform Admiral Nimitz of the bomb project and ask permission to choose a site for the 509th Composite Group and Manhattan Project operations. In the end, he chose Tinian. There was no room at Isley Field on Saipan and Guam didn’t have any runways ready to use. Lastly, Tinian was 100 miles closer to the target and provided better security for the secret.
The next man sent to Tinian was Col. Elmer E. Kirkpatrick Jr., Army Corps of Engineers, General Groves’ personal “go to” guy. Disguised as an Army Air Force engineer, he met with General Brigadier General Frederic von Harten Kimble, Tinian Island Commander, on March 27, who assigned the 67th Naval Construction Battalion to build whatever facilities Kirkpatrick requested, including the 1st Ordnance Squadron camp (later called the High Tech area) where parts for the bombs would be stored and some of the subassemblies completed; the three Atomic Bomb Assembly buildings and the two atomic bomb loading pits.
The first elements of the 509th Composite Group, which included not only the 15 Silverplate B-29s of the 393 Bombardment Group, and a variety of support groups, arrived at North Field on May 18th. The first shipment of cargo for the Manhattan Project landed at Tinian on Memorial Day.
On June 5, Col. Paul Tibbets Jr. commander of the 509th, arrived on Guam for meetings with General LeMay. On June 11, the first of the 509th’s Silverplate bombers arrived at North Field.
It had already been decided that the Little Boy, the uranium-based, gun-type atomic bomb, would not be tested. The scientist gave it a 100% probability of detonation. However, Fat Man, the plutonium-based, implosion-type atomic bomb, would require testing. That test took place on July 16 in the desert of Alamogordo, New Mexico. It was successful, shocking everyone present. Immediately following the test, the scientists and technicians who would assemble the bomb on Tinian were bussed from Los Alamos to California, where they joined the U.S. Army (sort of) and then flew on to Tinian.
The Trinity Test was conducted on July 16, 1945, proving that the plutonium-based, implosion type bomb, essentially identical to the Fat Man bomb dropped on Nagasaki, would work.
Potsdam Declaration
Word of the successful test were cabled to Truman at Potsdam, Germany, where he was meeting with British Prime Minister Winston Churchill and Soviet Marshal Joseph Stalin. The Potsdam Declaration, demanding the unconditional surrender of Japan, was issued on July 26. That same day, the USS Indianapolis arrived at Tinian after a ten-day run from California, carrying about half of the refined uranium for Little Boy, as well as the L-11 casing. The remaining uranium would be delivered by air.
Little Boy was ready for delivery to Japan by July 31, but they had to wait for clear weather. Orders had been issued that the bombardier had to actually see the target through his Norten bombsite before he could release the bomb. At first, LeMay’s weathermen predicted clear weather over Japan for August 5, then postponed to August 6, 1945, 78 years ago yesterday. Remembering Pearl Harbor, remembering the Bataan Death March, and remembering all the chances Japan had to quit the war but refused, Col. Paul Tibbets, piloting the B-29 Enola Gay, dropped Little Boy on Hiroshima on the morning of August 6, 1945. Once again, President Truman encouraged the Japanese to immediately accept the Potsdam Declaration to prevent another atomic bombing.
Marshal Stalin had a fit. America had beaten him to the bomb. He still wanted a piece of Japan, as he had half of Korea and piece of Germany. After throwing a tantrum, he ordered his generals to launch the invasion of Japanese-held Manchuria and prepare for an airborne invasion of Hokkaido.
The following morning, today August 7, 78 years ago, Tibbets, Admiral William Purnell, the Navy’s representative to the Manhattan Project, and Brig. Gen. Thomas Farrell, deputy to General Groves, met with General LeMay on Guam to discuss the Fat Man mission. Not unexpectedly, weather became a problem. A new front was moving toward Japan and they could not depend on clear weather after August 9. The bomb was not scheduled to be ready to drop before August 10. The critical question was whether to wait for the new weather front to move through, which could be several days, or move the mission up the 9th.
Dr. Norman Ramsey, the chief physicist on Tinian, said he could make it happen (even though there were some new parts that were not fully tested), but he could only give it an 80% chance of detonation. Because Admiral Purnell had prophesized that it would take two bombs, one dropped shortly after the other, to convince the Japanese to surrender. They agreed to the August 9 delivery date. Back on Tinian that evening, Col. Tibbets assigned Major Charles Sweeney, a non-combat-tested pilot, to fly the mission.
The Fat Man assembly team spent every minute of August 8 doing their very best to properly prepared Fat Man for delivery on the 9th, loading the bomb into the B-29 Bockscar.
Nagasaki
At 0348 in the morning, August 9, Chuck Sweeney, piloting the B-29 Bockscar, lifted off from North Field and headed north toward his primary target, Kokura.
That same morning, and unknown to the rest of the world, at 0100 Manchurian time, 0558 Tinian time, the Russian Army attacked the Japanese army of Manchuria, entering the war against Japan.
Unfortunately, for Sweeney, but fortunately for the people of Kokura, it was covered with smoke and haze, preventing the bombardier from seeing the target. Sweeney was forced to head for his secondary target Nagasaki, where he managed to drop the bomb at 12:02 p.m. After making a desperate landing at Wonton Airfield, Okinawa, Sweeney finally, after nineteen and a quarter tension-filled hours, landed back on Tinian at 11:06 p.m.
At 6:45 a.m. the following morning, August 10, the Japanese government transmitted its initial offer to accept the Potsdam terms to the Swiss and Swedish embassies.
Emperor Hirohito transmitted his surrender message to the people of Japan on August 15. Stalin’s armies were still driving toward Hokkaido. On the 16th, Stalin wrote to Truman, “Russian public opinion would be gravely offended if the Russian troops had no occupation area in any part of the territory of Japan proper.”
Truman, with another Fat Man being prepared on Tinian, was ready for Stalin, “Regarding your suggestion as to the surrender of Japanese forces on the island of Hokkaido to Soviet forces, it is my intention and arrangements have been made for the surrender of Japanese forces on all the islands of Japan proper to General MacArthur.”
Wisely, President Truman decided to leave Japan’s imperial system in place. Following Truman’s lead, Gen. MacArthur, Supreme Commander for the Allied Forces, wisely chose to work closely with Emperor Hirohito toward the redevelopment of a unified Japan and a strong alliance with the United States. With that, Japan was guaranteed to remain a unified nation with their kokutai intact.
Therefore, the use of the bombs, at the time they were used, ended all the killing and provided for a strong alliance between Japan and the United States for a lasting “Peace in the Pacific.”
Had the bombs not been used, Japan would have been divided into a Russian, Communist North Japan and an independent South Japan, just like Korea, and there never would have been a Japanese tourist industry for our islands to enjoy.
Furthermore, had Truman not used the bomb, what would he tell the mothers of all the boys who died in combat before Japan could be forced to surrender months later through starvation and continued conventional bombing?
Although the United States has experienced two “proxy wars” in Asia, the Korean War and the Vietnam War, there have been none since — sixty years of peace.
Today, once again, the Indo-Pacific region is facing troubling days. North Korea is threatening a nuclear attack against Guam, causing the United States to begin refurbishing old air bases in the region, just in case.
China is attempting to impose its will on Taiwan.
Both are serious causes for concern among all Pacific people. We can only hope that common sense will prevail, and Peace in the Pacific will be maintained.
An educator and historian who resides on Tinian, Don A. Farrell is the author of many books, including “Tinian and the Bomb.”
