Episode 44: the First Atoll
In November 1943, as the battle for Bougainville raged and MacArthur and Halsey continued to ram their way up the Solomons toward Rabaul, Nimitz was preparing to begin his career defining drive through the central pacific. Rather than skirting the pacific rim in a series of major land operations characterized by island jumps of tens to hundreds of miles like MacArthur was doing, Nimitz had an entirely different approach. Much like the Southwest Pacific theater, his campaign would involve seizing key islands for the sake of their airfields.
Unlike the Southwest Pacific however, where the islands were mostly tropical jungles and big enough to allow for large land maneuvers, the central pacific islands were mostly coral atolls, tiny by any metric making the battles for them tight, claustrophobic affairs with little room for maneuver.
The first step would be to take footholds in the Gilbert islands. Way at the periphery of the Japanese empire, the Gilberts had been British colonial possessions but were gradually conquered and consolidated by the Japanese between December 19411 and March 1943. Almost as soon as they had planted their flag on these miniscule spits of land the Japanese began preparing their defenses. They began pouring concrete and sighted guns of all calibers up and including 8 inch coastal defense guns brought in from Singapore along the expected avenues of approach, fortifying beaches against amphibious assault. By September 1943 the defenses were complete.
Nearly all of the islands in the Gilberts chain are Atolls meaning they are mostly low and flat, with a max elevation under 16 feet. Island vegetation consists mostly of coconut groves, screwpine, and scrub. This combination of coral, flat features, and easily cleared vegetation makes them ideal for constructing airfields. Hence the airbase constructed on Betio in the Tarawa Atoll.
They were a part of Admiral Keiji Shibosaki’s Yogaki defense, meaning waylaying attack. The pillboxes and bunkers were only the final part of the defense in depth which included four layers. The first layer utilized long range bombers to disrupt american naval operations. Following that short range aircraft based in Truk were meant to continue the aerial attack. The next layer committed Japanese surface vessels to direct action against the US pacific fleet. And finally, the fourth layer, a swarm of submarines meant to overwhelm the American vessels. Only after defeating all of those methods would the defensive works manned by infantry be utilized to defeat the Americans at the waterline.
Unfortunately for Admiral Shibosaki the Americans had begun disrupting his defense in depth both directly and indirectly. Operations in the upper Solomons drew off surface vessels, aircraft, and troops that he had been counting on to interdict the US landing forces. Thanks to the landing at Bougainville, Halsey’s audacious carrier strikes on Rabaul, and the battle of Empress Augusta Bay there was very little left to defend the gilberts besides the men on the ground and some aircraft left at Truk. The plan was directly opposed on September 19th when the carriers Lexington, Princeton, and Belleau Wood raided Tarawa destroying tugboats needed to move water obstacles, as well as aircraft parked on the airstrip.
Three men named Smith would be responsible for the seizure of the Gilbert Islands. In overall command was Lieutenant General Holland “Howlin’ Mad” Smith USMC of V Amphibious Corps. Subordinate to him he had Major Generals Julian Smith, commander of the 2nd Marine Division, and Ralph Smith, commander of the 27th Infantry Division. They would not land troops on every island however, only Makin and Tarawa atolls. The Army would take the more lightly defended Makin Atoll and the Marines the more heavily defended Tarawa Atoll, specifically, the island of Betio.
Only light resistance was expected at Makin; around 700 Japanese were garrisoned on the island. Tarawa on the other hand was much more heavily defended with nearly 5000 men and the defensive works to protect them including dozens of coastal defense guns. Unfortunately, US forces had very little idea of what to expect when they began planning the Gilberts offensive and had to engage in extensive reconnaissance to develop the operational picture. This would also be the first time the US military engaged in Atoll warfare. Though the department of the Navy had long theorized about the prospect and the Marines considered it to be essentially their raison d'etre they had little operational experience to draw on except lessons learned in the Solomons by the Army, Navy, and Marines.
The lessons learned concerning amphibious operations were many and included the following summarized and abridged. These are drawn from a document Titled “Movement of a Task force by Small Landing Craft” by LTC E. S. Watson of the 43rd Infantry Division written in the aftermath of their occupation of the Russell islands. He writes, with some humor, that these lessons were “...the product of careful study, and in some cases trial and error. They may be of value.” They are:
Make preliminary practice loadings and landings under conditions approximating the landing.
Aerial photographs are almost a necessity.
Every possible measure should be taken to determine the marine hazards of the destination.
A thorough and energetic supervision should be exercised over the handling of supplies and equipment. Apparently, the imminence of enemy contact is inversely proportionate to the consideration of property. G-4’s (Division logistics officers) have noticed that property will disappear.
At least 25% of all rations transported will be lost, largely through the effects of sea and weather.
Before a unit leaves the states, crates and boxes should be constructed for all impedimenta. This does not mean the usual hasty crate or cartoon. Sturdy reinforced boxes built by skilled technicians, reinforced with hardware, and furnished with carrying devices will pay their way many times.
In planning the forward movement of troops, retain enough in the rear base to handle the loading of the balance of cargo. Gradually work the rear troops forward as the labor requirements diminish.
Establish provisional labor companies for handling cargo as soon as the beachhead is established. Do not depend on intermittent details or the passenger troops.
Unload craft rapidly. Devote all energy to accomplishing the unloading and let dispersion wait until the boats are clear; the boats are a more renumerative target than a pile of rations.
Use dim colored lights at night for LCTs to guide on as they approach the beach.
An artillery battery with three units of fire can be transported in two LCTs with prime movers and guns.
An infantry combat team with five units of fire, fifteen days rations can be transported in four destroyers and four LCTs.
One LCT will carry 175 tons of rations or 700 drums of gasoline.
Equipment to be loaded should be staged the night before the landing.
Be prepared for sudden changes of plans in the landing. Waves of troops will not always land where they should. Companies may become mixed and the heavy weapons may not be there when they should be. Battalion com-manders should be ready to make rapid reorganization of their strength, without halting the forward movement.
Treasure your road net.
Coconut groves make good concealment for bivouac areas.
Americans have yet to learn how to deal with natives. They Should be respected and ignored, their villages should be put off limits, and their services secured only under exceptional circumstances and then by an experienced representative.
The principles of combat are just the same as they ever were.The book is still right. Island warfare differs only in that your lines of communication for supply and evacuation are a little more precarious. So are the enemy's.
…and finally.
Engineer road equipment should be in the first echelon to commence road building and road repair immediately.
These lessons would be taken into account during the planning phase but something still had to be done about the lack of intelligence. This was rectified through three primary means. The use of surveillance aircraft to take numerous photographs of the island including landing areas, beaches, lagoons, reefs, channels, and the exact locations, type, and strength of defenses. The employment of submarines to take horizontal photos as well as obtain environmental data regarding surf, tides, winds, and currents. Lastly, fifteen former British residents of the islands were found who could speak to the conditions of the islands.
The extensive intelligence preparation of the battlefield yielded important operational results one of which was the revelation that the seaward facing defensive works were simply too significant for landings to be attempted from the open ocean, or southern facing beaches, They would have to assault from the northern, lagoon facing beaches. That is not to say these beaches were undefended, they were, and a solution was still needed to be able to penetrate the north facing beachworks as well as navigate the shallow lagoon during low tide. They found their solution in the Amphibious tractor commonly called AMTRACS or simply alligators.
These amphibious tracked vehicles could get through the protective wire and log obstacles constructed by the defenders as well as roll over coral outcroppings in the lagoon. Unfortunately, the 2nd MArine Division only had seventy five at its disposal. So Howlin MAd Smith went to bat for his men, returning to Washington to argue for more vehicles with Admiral Turner, commander of V Amphibious Force. The navy was reluctant to procure the AMTRACS but ol’ Howlin MAd gave him an ultimatum, “No AMTRACS, No Operation.” Shortly thereafter 50 AMTRACS were found available in San Diego to be transported to Samoa where the landing force could pick them up en route to their invasion.
The Japanese defense of Tarawa Atoll was described by one report as “a small island edition of the German West Wall, with one extremely important difference -- no depth.” Japanese defensive doctrine in its outlying islands was centered around defeating the invading force at the waterline. Theoretically this could be done in two ways. First and most obviously, by conducting a perimeter defense around the entire coast. Obviously this is not possible on larger islands, as was the case in the Solomon islands. In that case, Japanese doctrine called for a counterattack on the invading force like “an electric shock… at the proper moment to annihilate the enemy by close range fire, by throwing hand grenades, and by hand to hand combat.”
On Betio effectively every inch of coastline was defended by some sort of gun or bunker allowing the Japanese to execute a perimeter defense. Every 25 to 50 yards in a line circling the island the defenders constructed pillboxes roughly 50 yards from the waterline supported by heavier batteries and bomb proof shelters placed between them. However, they also maintained a decentralized mobile reserve in order to rapidly drive the invader back into the sea.
Against them were arrayed the 18,600 men of the 2nd Marine Division, 10,000 of which were slotted to land on Betio, the remainder were held as Corps reserve to land at either Makin or Betio as operational needs emerged. In late October V Amphibious Corps embarked from Wellington New Zealand under the auspices of a Training exercise at Hawkes Bay on the Eastern side of the North Island. The deception was to prevent news of a large troop movement from garnering any surprise and only the highest ranking officers in the invasion force knew it was a ruse. Soldiers and marines told their sweethearts they would be back in a couple and weeks and even the government of New Zealand was fooled. The American force went through all the movements of legitimately conducting an exercise including hiring services to haul equipment to the training site. They just never showed up.
Instead, they began sailing North toward Vanuatu where the invasion force would gather and wait until the conditions at Betio were favorable, meaning when the tide would be high enough for the landing craft to get through but also receding so that there would actually be a beach for the men to land on. November 20th was determined to be the ideal date for a landing when those conditions would be met. So on the night of November 19th the invasion force of three battleships, five cruisers, nine destroyers and 17 troop and cargo supply ships was waiting to the west of Tarawa Atoll for the assault to begin. At the same time the Makin invasion force was preparing to land troops at that island.
The landings at Makin went about as smoothly as a contested amphibious landing can go. The men of the 69th Infantry Regiment, 27th Infantry division landed on the north and west shores of Butaritari Island of Makin Atoll and emt no resistance. Despite relatively light defenses it took 69th Infantry three days to fully secure the island and declare it taken, mostly because the troops were green and shaky. Just as happened in New Georgia, men who were untested in combat and unfamiliar with the terrain could be easily halted by relative small defensive positions and spooked easily. This initial trepidation soon faded however and by the second day the Soldiers had seasoned a bit and were able to more effectively dig out the defenders.
The army only suffered 66 men killed and 185 wounded. The great majority of the casualties sustained during the Makin operation occurred when a submarine attack on the USS Lanscome Bay detonated the aircraft carriers bomb storage area. The blast destroyed the rear third of the ship and killed more than 650 Sailors almost instantly. This embittered the Navy and admiral Spruance who felt that the inefficiency with which the army took the island forced the Liscombe Bay to remain, and provided the Japanese submarine with the opportunity to launch the torpedo attack. Things would go quite differently at Tarawa Atoll.
At 3:30 in the morning of November 20th the sea bombardment of Betio would begin. As the marines descended the cargo nets into their landing vehicles, bellies full of the now traditional pre-battle meal of steak and eggs, the Japanese shore batteries began to open up. In response, the battleships and cruisers of the invasion force turned their main guns toward Betio to engage in counter battery fire. The USS Maryland managed to strike a munitions bunker for one of the 8 inch coastal batteries killing hundreds and igniting an absolutely volcanic explosion. Before dawn three of the island's four big coastal guns had been destroyed.
Just about two hours after the artillery duel began the guns of the invasion fleet went silent. The island glowed orange and smoke bellowed into the air. Silence fell over the seas in anticipation of the aerial assault that was to follow. Dozens of Avengers and Dauntless dive bombers descended on the island, destroying yet more japanese defenses before heading back out over the horizon. By 6:10 in the morning the aircraft had cleared and the shore bombardment could resume.
This time the battleships really let them have it. In each salvo the Battleships launched eight sixteen inch armor piercing shells weighing 1500 pounds each at the island. For three hours the ships lobbed shell after shell at the island. Despite this, much of the Japanese defenses remained intact. The marines churning toward the shore in their Amtracs would still face much resistance. To amke matters worse the water level didn’t seem to be rising. Planners had expected five feet of water over the reef but as the minutes ticked by the water stayed low. A neap tide had struck. Something of an unusual hydrological phenomena where during certain conditions high tide doesn’t bring the normal amount of water with it. There would only be three feet of water over the lagoon making traversing it much more difficult and force marines to disembark and wade hundreds of yards to shore.
The neap tide wasn’t completely unforeseen. The old hands from the British colonial days had warned that a neap tide was likely but navy and marine planners had convinced themselves they would get the depth they needed in the lagoon. They were sorely mistaken and the marines going ashore would pay the price.
While the Amtracs chugged along toward the shore, navigating the coral outcroppings as best they could, the Japanese fired everything they could at them from direct machine gun fire to mortars to larger artillery. The unarmored amtracs could hardly withstand the Japanese fire and many of them sputtered and burned out hundreds of yards from the beach forcing the marines to begin the slow wade to shore from wherever they happened to stall out. Those amtracs that did make it all the way to shore were generally so badly riddled with holes by japanese small arms fire that they couldn’t make it back to the landing ships to pick up more men.
After the first wave made it ashore the men were pinned on the beach waiting for more men to come ashore. The problem was too many amtracs had been destroyed so there was nothing to carry the waiting marines to shore after the first three waves. So the men did what they had to do and waded all the way from the lagoon edge to the beach, sometimes as far as half a mile. With half of their bodies exposed these men proved easy targets for the Japanese who could pick them off at their leisure as they waded in.
By noon a sizable number of marines had gotten ashore but the situation remained desperate. Colonel David Shoup did his best to organize the landing force and established a headquarters in the vicinity of the pier that jutted out into the water about half down the length of the landing beach. The Japanese had established firing points and machine gun nests all along the pier so the marines had to clear them out by fire before even turning their attention inward. Even then, the seawall was all that separated the opposing forces who could be as close as fifteen yards from one another, constantly exchanging fire and grenades. From his command post at the base of the pier Shoup would organize the first assaults inland under these withering conditions and for it he would eventually be awarded the medal of honor.
At 1:30 in the afternoon, knowing the outcome of the battle hung in the balance, General Julian Smith asked General Holland Smith to commit the corps reserve. The corps commander agreed, making the 1st battalion 8th marines, who had been waiting in their boats since before dawn, immediately available. Several Stuart and Sherman tanks had also made it to shore which helped the marines establish their beachhead but by nightfall only one remained operational.
As the sun set on November 20th roughly 5000 marines had gone ashore but only 3500 of them were still combat effective. They had carved out two footholds separated by about 600 yards but which penetrated up to 250 yards inland, occupying part of the airfield. In other areas the beachhead was much more precarious, pushing on a few yards up from the beach. Though their day’s fighting had been hellish and deadly, those marines that had made it ashore fought tenaciously allowing them to penetrate so far beyond the seawall in some places. The men ashore began digging in where they were knowing that when darkness fell the Japanese would launch their characteristic counterattack.
The expected counterattack never came though. All through the night the men waited but only small, uncoordinated attacks came and the occasional mortar round. During the initial bombardment the island's telephone network had been knocked out so Admiral Shibeseki had no way of coordinating with his subordinate headquarters. What runners he did send out were quickly picked off by marines who now had excellent observation and fields of fire over most of the island.
While the Japanese did their best to put together ad hoc counterattacks the invasion force did not simply rest and wait for morning, no, the Americans were busying themselves bringing artillery up and reserves while evacuating the dead and wounded. When dawn broke the marines 75mm guns were on the beach and ready to start pounding japanese positions. They would come in quite handy because dawn also marked the start of raking japanese machine gun fire emanating from blockhouses just inside the seawall. As men began wading in from the reef’s edge the terrible fire resumed and the marines ashore did everything they could to silence it. They tried indirect fire from their howitzers but seemed to only dent the concrete. They tried calling in naval aviation to dive bomb the bunkers that proved ineffective. Destroyers remained close to the reef edge to provide covering fire and suppression with their 5 inch guns but even that didn’t put an end to the Japanese fusillade. Eventually they realized that only by directly closing and attacking by fire could they silence the Japanese guns. So that's what they did.
If a pillbox was still firing after being pounded by artillery, naval gunfire, and aerial attack the marines had myriad options to neutralize it including direct fire, flamethrowers, tanks, and bulldozers. The first option was to try and knock it out with one of the tanks. This sometimes worked but more often than not it simply chonked a big whole out of the side of the Japanese concrete fortresses. From the newly exposed hole marines could jet a stream of flame or lob in grenades and fire frantically inside. If that wasn’t feasible the next best thing was to close with the bunker, bring a couple of engineers, and toss in a few charges of TNT through the gunport or a ventilation shaft. Finally, if a bunker proved exceptionally well defended one last option remained; the bulldozer. This was the fate of Admiral Shibasaki’s command post. The dozer rolled in under a storm of covering fire, blade raised to protect the drive from enemy fire, until it was close enough to begin its work. The operator would lower the blade and begin shoveling sand on top until the whole thing was buried. The marines then poured gasoline and dropped grenades down the ventilation shafts for good measure.
That was how the second day on Betio was spent by the marines. Slowly and methodically clearing out bunkers, entrenchments, and pillboxes until the island had been cut in half. That day 600 more marines flowed onto the island while 340 were killed or wounded attempting to cross the lagoon. Despite the casualties mounting in teh lagoon adn on the island progress was being made. The third day would be characterized not by the ferocity of the second day but by cold, systematic, precision. The men fighting on Betio now had two days of experience, a veritable lifetime in direct action against a determined enemy, and they knew their business well. Having split the island in twain the day before the third day’s objective was to eliminate “the Pocket.” The 600 yard wide gap between the two halves of the american invasion force. It took the better of the day but eventually the pocket was reduced and the Marines could go into the final day with only the tail, or eastern, end of the island remaining in enemy hands.
The night between the third and fourth days the Japanese made their expected banzai charges but they had little effect and were repulsed. Following dawn naval aviators swooped down to bombard the remaining Japanese positions before fresh troops were committed to mopping them up. The 3rd Battalion 6th marines with the tanks Colorado and China Gal pushed forward in a crackling of gunfire gaining 150 yards in under an hour. Japanese resistance was breaking and by 1:00 in the afternoon Betio, and essentially all of Tara Atoll was in American hands. Admiral shibasaki had proclaimed that a million men couldnt take the island in a hundred years. General Smith did it in three and half days with 10,000 men.
The battle of Tarawa as it is most commonly referred to, was a bloody and somewhat scandalous affair. 1000 Americans died and 2,000 more were wounded in the invasion for 4690 Japanese killed. Days after the battle ended pictures of dead americans floating in teh surf were published in newspapers across the country. Why had so many young men died to take this miniscule spit of land in the middle of the ocean? The high casualties wound up being fodder for the Army-Navy interservice rivalry and for General MacArthur's political posturing. MacArthur and his surrogates were able to use the dead to bludgeon the Navy and lobby for full operational command of the pacific theater. Of course those in the halls of power knew MacArthur’s argument was bunk. They had seen how he handled the New Guinea campaign and knew he was no mastermind and saw the posturing for what it was.
There were of course lessons to be learned from the first amphibious invasion of an Atoll that would save lives in future operations. Among them were communications and joint fires coordination elements called Joint Assault Signal Companies, or JASCOS. Their purpose was to come ashore after the initial landings to coordinate naval gunfire, close air support, and coordinate beach head communications. They also helped beachmasters coordinate unloading cargo and directing shore-parties. On the flip side, new command ships were designed specifically to have the equipment needed to coordinate a land battle from the sea rather than using ad-hoc headquarters aboard battleships. Loading techniques were further refined as well. The Navy and Marines determined that rather than loading all of one item in one location on an LST items should be layered together so that if there was a sudden demand for , say, extra fuel oil, they wouldn’t have to unpack a whole LST’s worth of rations, ammunition, and lubricants to get to it.
Improvements in equipment were made to reflect the challenges faced on Tarawa as well. Exact replicas of the defenses constructed on Betio were constructed at firing ranges in Hawaii where different techniques were tested against them to see what was most effective. These results informed the designs of new hardware that would be constructed to send back out to the force including amphibious tanks and flamethrower tanks. An amphibious truck was developed to help ferry troops and supplies ashore when not under direct fire. A new innovation, if not a new piece of hardware, was the use of the Landing Ship Dock to carry LST already loaded with tanks as close to the landing zone as possible saving time and reducing logistical strain in the immediate run up to the battle.
The biggest lesson from Tarawa wasn’t in new methods for destroying pillboxes or improved landing techniques, it was the need for Naval Commanders to take land commander’s requests seriously. Had Admiral Turner listened to General Julian Smith and taken him seriously when he requested additional Amtracs, hundreds of Marines' lives could have been saved. Had Turner released all 100 Amtracs instead of only fifty there may well have been vehicles to take men ashore after the first wave. Most of the marines who were killed died while wading in from the reef edge. If there had been fifty more amtracs present at the battle many of them may well have been able to ride to shore rather than wade.
I understand Admiral Turner’s predicament, the additional amtracs would have to be loaded and transported on LSTs, which are slow and lumbering vessels. In order for the LSTs carrying the amtracs to arrive on time for the invasion they would have to leave before the main body and thus increase exposure to Japanese pickets. He worried this would alert the Japanese to the invasion force sooner or expose the LSTs themselves to bombardment. This is obviously a reasonable argument but I would counter that the needs of the invasion force should come first. In this instance I would argue that the risk was worth it. Reasonable people could draw different conclusions however.
Regardless, Tarawa had fallen and the Gilbert islands were essentially in allied hands by the end of November 1943. The Marshals were next in the docket for Admiral Nimitz beginning with Kwajalein in early 1944. The Empire of Japan and its Pacific thalassocracy was beginning to crumble. The Solomon islands were lost and the first outlying islands in the central pacific had been knocked off. Even if they didn’t see it yet, the writing was on the wall for the Empire of Japan. At this point defeat was inevitable.
