Hiyo-class aircraft carrier (commissioned 1941)
Imperial Japanese Navy
Ships: Hiyo, Junyo
Part Two
By March 1942, Japan had secured most of her strategic goals in the Pacific. Singapore, Hong Kong, Indonesia, Malaya, the Marianas, Wake Island... the list went on. Only the Philippines still held out, and it was clear that even they would not last long. Faced with this, the Japanese decided - unwisely but boldly, as it would turn out - to extend their defensive perimeter.
Japan's eyes now turned south-east, towards the Solomon Islands and New Guinea, and in particular the town of Port Moresby, which could serve as a useful staging point for further operations near Fiji and Samoa, and as a powerful airbase to interdict Allied traffic in the Coral Sea. Taking Port Moresby now became a priority on the Japanese list. It was now that the large number of operational fleet carriers in the IJN began to pay dividends. Originally, Admiral Yamamoto had considered sending all eight of the Kido Butai's fleet carriers into the Indian Ocean to find and destroy the Royal Navy's Eastern Fleet. However, in early March, he changed his ideas, and instead detached Carrier Division 6 to prepare for a seizure of Port Moresby in April, in an operation codenamed MO.
Kakuta's ships were chosen for the mission as they were possibly the least useful carriers in the strike force, being only 28-knot ships and carrying small air groups. Besides, they were not as experienced as, say, the queens in CarDiv 1, and so, if they were lost - but they would not be, of course - they could be spared more easily.
While Nagumo's six other flattops charged into the Bay of Bengal and sowed havoc through the first week of April, Hiyo and Junyo relocated to Truk to rest, conduct a short refit, and prepare for the operation. MO would finally get underway in late April. Unfortunately for the IJN, on 18th April, Vice Admiral William 'Bull' Halsey raided the Home Islands. TF 16, built around USS Enterprise, the survivor of Pearl, escorted TF 18, built around Hornet and Constellation, to a launch point hundreds of miles off Japan. There, watched over by their veteran older sister, the two apple green ships launched nearly three dozen B-25 Mitchell medium bombers towards Tokyo. The damage done was minor, but the mood in Japan was soured. Destroying the American carriers became a priority in Yamamoto's mind.
MO would, unintentionally, provide an opportunity for this. Lexington's TF 11 and Yorktown's TF 17 were waiting in the Coral Sea when the Japanese came. Over a multi-day battle, the two Japanese and two American fleet carriers would duel in the first carrier battle in history. Their solid battleship hulls providing a good measure of durability, Hiyo and Junyo would survive, albeit with heavy damage to Hiyo especially and severe airgroup attrition for both ships. In return, they would send Yorktown to the bottom, and maul Lexington with bombs and torpedoes. Nevertheless, Admiral Fletcher managed to thwart Kakuta's advance on Port Moresby, and save the town.
Carrier Division 6 would be unable to operate as a combat unit until August at the latest, and so they would not be able to sail with the Kido Butai when they set off for a small island in the Central Pacific to fight the much-desired Decisive Battle. It would be a mixed blessing.
Waiting for Nagumo's six fleet carriers at Midway were Enterprise, Hornet, Constellation - and, near miraculously, the still badly damaged Lexington, who had been sent to the battlefield a day after her peers thanks to Nimitz's insistence and Pearl Harbor's incredible dockworkers. On June 4th, they clashed in a titanic combined arms battle off the atoll. When the smoke settled, Lexington had succumbed to her wounds and gone to the bottom of the Pacific, and Hornet along with her. However, they would take Soryu, Hiryu and Akagi to the bottom, and bang up the Kaga and Shokaku. After a botched attempt to capture the atoll, Yamamoto returned to lick his wounds.
The battle left the US Pacific Fleet with Enterprise, Constellation, Saratoga and Wasp, while the IJN had Kaga, Shokaku, Zuikaku, Hiyo and Junyo. The Japanese offensives had been stopped at Midway. However, the odds were still not favourable. Nimitz found himself at a loss regarding what to do.