Buried the last of the Japanese Navy, the Fourth Theater of Operations directly faced the Ryukyu Islands.

The Ryukyu Islands are composed of more than 140 volcanic islands, with a total area of more than 4,000 square kilometers, and were vassal states of Shenzhou in the Middle Ages, and its kings paid tribute to Shenzhou every year, and had close economic and cultural exchanges with Shenzhou.

During the years of Japan's seclusion, it was an important bridge of trade and exchanges between Japan and China, so Japan allowed the Ryukyus to become independent until 1879, when it was officially incorporated into Japan's territory.

The Ryukyu Islands can be divided into three archipelagos, from north to south, the Amami Islands, the Okinawa Islands, and the Sakishima Islands.

The main island, Okinawa, is the largest island in the Ryukyu archipelago, with an area of about 1,200 square kilometers with a length of about 100 kilometers from north to south, about 30 kilometers at its widest point from east to west, and only 4 kilometers at its narrowest point.

The main cities are Naha, Shuri and Motobu Town, the northern part of Okinawa Island is mountainous, the south is open and flat hilly area, there are two natural harbors on the east coast of the island, Kinmu Bay and Nakajo Bay, the Japanese army built Naha Military Port, and there are four airports on the island: Naha, Kadena, Yomitan and Yonawara, which are important sea and air bases in the southwest of Japan.

A special type of structure on the island of Okinawa is the circular family tomb, which is made of solid stone, which can be found everywhere on the island, and the Japanese army has slightly modified it to become a strong fortification.

Okinawa is known as Japan's "national gate" because of its important strategic position in Japan's mainland defense, so the Okinawa landing battle is called the "Battle of the Gate".

After the Red Guard Corps occupied the Dutch East Indies and the Philippines, Okinawa's position in the defense of the mainland became more prominent, and as far as Japan was concerned, once Okinawa Island was lost, the sea and air supremacy of the mainland, Korea, and the coastal areas of China would all be lost.

The sea line of communication to Southeast Asia, on which Japan relied for its survival, was completely cut off, so the Japanese army base camp judged that the Red Alert Empire must land on the island of Okinawa before attacking the Japanese mainland, so the Japanese army attached great importance to the defense of Okinawa.

Since the fall of the Mariana Islands, emphasis has been placed on strengthening the defensive forces and fortifications of Okinawa.

At present, the Japanese garrison in the Ryukyu Islands is the 32nd Army, with a total of four divisions and five brigades, with Okinawa Island as the focus of defense, and the commander of the 32nd Army, Lieutenant General Ushijima Mitsuru, personally commanding the 9th, 24th, and 62nd divisions and the independent 44th brigade for defense.

In accordance with the operational policy adopted to lure the enemy to a deep area without naval and air fire support, and to destroy him by virtue of a predetermined position, the Japanese army deployed 80 percent of its forces in the southern area, centered on Shuri.

Only a few symbolic forces were deployed in the northern and coastal areas. The strength of the Japanese army on Okinawa consisted of two divisions and one brigade of the army, plus some garrisons of the navy and marines, totaling about 100,000 men.

In order to ensure the defense of Okinawa Island, the Japanese army base camp also drew up a decisive battle plan for the air force codenamed "Operation Sky," and concentrated a total of 3,000 combat planes of the army and navy, of which more than half of the total number of suicide planes were deployed in Treasure Island, Ryukyu, Kyushu, and other areas.

Prepare to carry out a fierce surprise attack on the fleet and transport ships of the Red Guard Corps when it lands on Okinawa Island, and cooperate with the 32nd Army on the island to crush the landing of American troops.

The Japanese Navy has also deployed hundreds of suicide motorboats and man-operated torpedoes on Okinawa and its nearby islands to carry out surface and underwater special assault operations against the Red Guard Navy.

In the face of the Japanese who were actively preparing, the Fourth Theater of Operations also did its best and went all out.

The Fourth Theater of Operations first abandoned military action against Treasure Island, and directly skipped the island of Peleliu, which had no attack value, and set its sights directly on Okinawa.

When the Fourth Theater was preparing to capture Iwo Jima, the Supreme Command of the Red Guard Corps had long made it clear that the Fourth Theater would begin preparations for the capture of the Ryukyu Islands.

After the capture of Iwo Jima, the Fourth Theater also submitted a prepared Okinawa battle plan, which was approved by Ling Liang.

The forces planned to participate in the attack on the Okinawa Islands include the entire Second Marine Corps, an airborne division, and an air cavalry division.

The size of the landing force is 150,000, and the Second Marine Corps alone has four fully equipped marine divisions and several independent marine brigades, with a total strength of 120,000.

The navy participating in the operation covered all the naval and air force units of the Fourth Theater, and the main warships of the Xuanwu Fleet were all dispatched, including three nuclear-powered aircraft carriers, two Pluto-class battleships, four dreadnought second-class battleships and four dreadnought-first battleships, and more than 100 cruisers and destroyers.

The amphibious landing fleet, which has the largest force structure in the Fourth Theater, was also dispatched in its entirety, with more than 100 amphibious dock landing ships, hundreds of tank landing ships, and troop transport ships.

The main force of the amphibious fleet is four amphibious assault ships with a displacement of more than 45,000 tons and 16 amphibious assault ships of the old class.

Counting all the logistical supply ships and frigates, submarines, and fire support ships, the number of all ships participating in the battle is 1,200, including 300 third-generation fighters and 400 helicopters.

The total number of troops invested reached an astonishing 450,000 troops, which was the largest number of troops invested by the Red Guard Corps in a war since the Pacific War.

Under the cover of night, the three aircraft carriers dispatched a large number of carrier-based aircraft to launch air strikes on the Japanese air bases and suicide torpedo motorboat bases on Okinawa and Kyushu islands.

Japan has amassed a large number of aircraft, which is still a great threat to the fleet, and the first step in the plan is to destroy as much as possible the Japanese fighters and seize air supremacy in an all-round way.

Although the Japanese were very vigilant and installed many radars on their homeland, these radars were generally ineffective, and the distance of the fighters was found to be even within the range of the anti-radiation missiles of third-generation fighters.

Even if the Red Alert Navy did not prepare anti-radiation missiles, the Japanese radar would hardly be able to approach a single third-generation fighter from a distance of five kilometers.

The air raids went so smoothly that the Japanese airfields on the islands of Kyushu and the Ryukyu Islands were destroyed on the night of three days before the start of the day.

That morning, it was determined from satellites that the air raids at night had destroyed at least most of the planes in the Japanese airfields, and that the number of warplanes that Japan could take off would not exceed 1,500.