World War II at Sea: A Global History by Craig Symonds reminds us how painful it was to be a grunt in the Pacific:
The Marines went ashore on Peleliu on September 15[, 1944]. The landings were difficult and the casualties substantial. Nevertheless, the Marines advanced inland and within three days they had secured the critical airstrip. That, however, proved only the beginning. Geologically, the island of Peleliu was dominated by a series of limestone ridges honeycombed with caves and tunnels that were impervious to aerial bombing or naval gunfire. The ten thousand Japanese defenders withdrew into those caves, determined to make the Americans pay in blood for every yard of soil. Amid temperatures that occasionally exceeded 115 degrees, men of the 1st Marine Division, soon reinforced by the U.S. Army’s 81st Division, had to go into the caves and take out the defenders one at a time. It took ten weeks for the Americans to clear the island, and they did so only at a great cost to both sides. Virtually all ten thousand Japanese defenders were killed—only two hundred were taken alive. American losses, while lighter, were nevertheless painful: a thousand killed and five thousand wounded—greater than the losses at Tarawa.
In terms of being an empire with the ability to move troops and supplies from place to place, Japan was essentially beaten by the end of 1944, says the author:
In December, on his inaugural patrol as skipper of the Flasher, George Grider sank four tankers displacing 10,000 tons each. The tankers, very likely filled with volatile crude oil from Java or Borneo, “disintegrated with the explosions.” It was so spectacular a sight that Grider allowed his crewmen to come topside two at a time to watch them burn. Only a few days later, the Flasher sank three more tankers off Indochina. As a result of such attacks, oil became so scarce that the Japanese began fueling their ships with soybean oil. They confiscated the rice crops of Indochina, causing widespread starvation, in order to turn the rice into biofuel. In effect, American submarines were doing to Japan what German U-boats had failed to do to Great Britain: starve it of the essential tools of war.11 By late 1944 Japan was running out of ships altogether. In the last two months of the year, Japanese ship losses actually declined from more than 250,000 tons a month to about 100,000 tons a month, not because American submarines had become less efficient but because fewer and fewer Japanese ships put to sea at all. Lacking sufficient transports and tankers, the Japanese (like the Italians in 1943) turned to using submarines and barges—even rafts—as supply vessels. By the end of the year, American subs were literally running out of targets.
This was foreseen earlier in 1944:
The American conquest of the Marshall Islands had been so swift and one-sided that it encouraged Nimitz and the Joint Chiefs to consider bypassing Koga’s main base at Truk altogether. It seemed a bold move at the time, for Truk had been the principal Japanese base in the Central Pacific since 1942. In fact, however, it was not nearly as well fortified as the Americans thought, for the Japanese had never quite believed the Americans would get that far. Now that they had, Nimitz and Spruance concluded that the Fifth Fleet could leap past it nearly fifteen hundred miles, all the way to Saipan in the Marianas.
Having penetrated the inner defenses of the Japanese Empire, the Americans were now in a position to block Japan from the essential resources of the South Pacific. That could be accomplished by seizing either the island of Formosa or the Philippines. The American chief of naval operations, Ernie King, strongly preferred Formosa. It was, after all, a single island, albeit a large one, as opposed to the more than seven thousand islands that made up the Philippine archipelago. Then, too, from Formosa, the United States could more easily supply their Chinese allies on the mainland. Dutifully arguing the navy’s position, Nimitz suggested that the Philippines could be bypassed and cut off as Rabaul and Truk had been.
Since the Japanese couldn’t supply the islands that they’d previously conquered, the mid-level analysts in the U.S. Navy wanted to bypass most of the islands, and the horrific battles that would inevitably ensue after an invasion, in favor of taking only places that could directly help with an invasion of Japan or support of allies in China. According to the author, Roosevelt and MacArthur wanted to liberate the Philippines for personal political advancement, despite the country’s military irrelevance. The Battle of Luzon alone cost more than 215,000 lives, essentially to no purpose if we believe this book. The battle was essentially won by March 1945, less than six months before the war ended.
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