Operation AI is the original name given by the Imperial Japanese Army during World War Two for the assault on Pearl Harbor on the 7th of December in 1941.
Japan wanted to expand their empire and was in need of raw materials. From 1931 on they waged war in Asia. In 1931 the Japanese invaded Manchuria and created the puppet state Manchukuo. After this they detached the province of Jechol from China during operation Nekka. Inner Mongolia followed shortly after in 1933 which was the start of the second Sino-Japanese war. The latter was a huge war with over 5,5 million Chinese soldiers versus over 4 million Japanese.
After the Americans placed an Oil and Steel embargo on Japan in 1941. Japan was in dire need of raw materials to keep the war machine going. President Roosevelt refused to speak with the Japanese diplomats as long they had an army in China. Japan decided to prepare for a strike on heir number one threat for expansion in Asia.
Pearl Harbor was the base of the American Pacific Fleet, the only major power in Asia that could interfere with the Japanese plan to invade the islands in the Pacific.
The Japanese Emperor insisted on diplomacy and months of talking followed. Emperor Hirohito did not approve the attack plan until the 5th of November in 1941 although the Japanese attack fleet left on 26th of November the same year.
In the early hours on 7 December in 1941 the Japanese fleet showed up in a surprise attack at Pearl Harbor to demolish the Pacific Fleet and give freedom of movement for Japanese military actions in the Pacificand on the mainland in Asia.
Next to 7 aircraft carriers they had 23 submarines, 2 battleships, 3 cruisers, tankers and 5 mini submarines. With over 180 planes in the first wave they hit the Pacific Fleet with torpedo’s planes, bombers and fighter planes. The sailors where totally surprised and unfortunately had an insufficient amount of anti aircraft guns.
On the second and last wave the Japanese used more than 170 planes spread out in 3 groups, like the first wave.
The surprise had worn of by now and this time the sailors and soldiers were prepared for the coming attack.
After the attack the Japanese fleet left the battle site, leaving the Pacific Fleet behind in the harbour with 18 American ships damaged or destroyed and more than 2400 American casualties. The sinking of the naval battleship USS Arizona was responsible for the bigger part of the casualties on this day. More than 1000 men lost their lives on this battleship.
Japanese operations this day ranged much further than the attack on Pearl Harbor. The Japanese army attacked Hong Kong, the Philippines, Malaya and Thailand, all on December the 8th all on the same day as the attack on Pearl Harbor. Due to different time zones the attack on Pearl Harbor took place on the 8th of december in Japan. On December the 13th 1941 they invaded Borneo and on the 17th they attacked the Netherlands East Indies.
Unfortunate for the Imperial Japanese Army the American Aircraft Carriers did not anchor in Pearl Harbor at the time of the attack. They would regret this later on during the Battle of Midway. As second they forsake to destroy the huge fuel depots on Pearl Harbor, it would have taken months to rebuild enough fuel for the Pacific fleet to go to war again in the Pacific.
Due to the fact that the Germans, Italians and Japanese signed a pact, Hitler gave a declaration of war to America on the 11th of December in 1941, and to China on the 9th of December in 1941.
The naval battleship USS Arizona sank in the harbour and lies on the bottom until today. The watery grave is a memorial which can be visited by boat.
Next to The USS Arizona is the USS battleship Missouri, it did not participate in the attack on Pearl Harbor for it was commissioned in 1944, but it served the US Navy until 1992. A little bit further lies the submarine USS Bowfin SS-287. Today a museum. The Bowfin was laid down on July 1942, also after the Japanese attack and served off and on until 1971.
During the war it was active in the Pacific and sailed nine patrols. It sank 14 ships and assisted in the sinking of one more. Unfortunatley it sank an unmarked Japanese ship on its seventh patrol, the Tsushima Maru which had almost 1500 civilians on board including more than 750 schoolchildren, only 59 children survived. It was restored in 2004 and is now open for public to visit.
LandmarkScout thanks Marcel Langeslag and Peter Vermeulen for providing the photos for this article.