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H-026-1: Operation Flintlock—The Invasion of Kwajalein, 31 January 1944

Kwajalein Operation, January-February 1944
Sailors on board USS Bolivar (APA-34) receive final instructions before landings on Roi Island, Kwajalein Atoll, 31 Jan. 1944. A chart of ship-to-shore movements for Roi and Namur Islands is on exhibit at right (80-G-57950).

H-Gram 026, Attachment 1

Samuel J. Cox, Director NHHC

February 2019

With the capture of Tarawa and Makin Islands in the Gilbert Islands at the end of November 1943, the U.S. prepared for the next move, the invasion of the Marshall Islands, the capture of which would be key to sustaining the U.S. drive across the central Pacific and ultimately to Japan. However, the bloodbath on Tarawa gave everyone pause. Despite the U.S. having overwhelming superiority in all domains, the Japanese defenders on Tarawa had fought courageously, almost to the last man, and made the U.S. Marines pay dearly to take the island. Almost as many Marines died in three days of fighting on Tarawa (about 1,000) as died in five months on Guadalcanal. The U.S. Navy suffered severe losses off Makin Island as well.

Press reporting of the capture of Tarawa was highly negative, and there were significant recriminations and repercussions within the U.S. military. Given the high casualties for such a small piece of ground, many questioned the wisdom of the U.S. Navy’s “island hopping” strategy. One influential critic in particular was General Douglas MacArthur, who advocated that the Central Pacific strategy be abandoned in favor of his advance up the northern coast of New Guinea toward the Philippines.

Despite criticism from many quarters, including from families of those killed on Tarawa, Admiral Chester Nimitz remained steadfast, even after he flew to Tarawa on 25 November 1943, only a couple of days after it had been secured, and saw first-hand the high cost and carnage involved. Nimitz directed that an extensive “lessons learned” effort be undertaken and that maximum effort to incorporate those lessons take place before the invasion of the Marshall Islands (see also H-Gram 025). One of the most influential of these lessons-learned studies was completed on 30 November 1943 by Rear Admiral Richmond K. Turner, commander of the Amphibious Forces in the capture of Tarawa and Makin. (Turner would also command amphibious operations in the Marshalls.) Turner determined from accurate intelligence that the key island in the Tarawa Atoll, Betio, had been greatly reinforced in the three months leading up to the attack, the lesson being that it was important not to give the Japanese advanced indication of impending attack. (This would seem self-evident, but it was easier said than done.) Turner also determined that the next invasion would require more and better aerial reconnaissance; more submarine scouting; pre-landing reconnaissance and obstacle demolition; more ships, especially destroyers for on-call gunfire support; more landing craft; three times as much pre-landing bombardment and three times as much ammunition; and numerous other technical and tactical changes. On 2 December 1943 Vice Admiral Raymond Spruance, Commander of the Fifth Fleet, approved Turner’s recommendations. Admiral Nimitz’s s approval was soon to follow.

Although by November 1943 U.S. Navy carrier forces in the vicinity of the Gilberts and Marshalls had overwhelming superiority, the lack of experience in many of the aviators and flight deck crews showed. During November 1943, of 831 planes aboard aircraft carriers in the central Pacific, 73 were lost to operational accidents. (Although the new Hellcat fighters were great airplanes, they turned out to be prone to blown tires on recovery aboard the carriers.)  However, in keeping with Admiral Nimitz’s principle that the way to gain combat experience was through combat, Nimitz wasted no time in ordering a series of fast carrier strikes on the Marshall Islands within days of the fall of Tarawa and Makin.

The fast carrier force assigned to attack the Marshall Islands was designated Task Force 50, under the command of Rear Admiral Charles A. “Baldy” Pownall. He also retained command of Task Group 50.1 with the new Essex class carriers Yorktown (CV-10) and Lexington (CV-16); the new light carrier Cowpens (CVL-25); four heavy cruisers, including San Francisco, New Orleans, and Minneapolis, all having been repaired after severe damage during battles off Guadalcanal and given improved anti-aircraft capabilities; and a light anti-aircraft cruiser. TF 50 would also include TG 50.3, commanded by Rear Admiral Alfred E. Montgomery, with the carrier Essex (CV-9), the battle veteran Enterprise (CV-6), the new light carrier Belleau Wood (CV-24), one heavy cruiser, two new light cruisers and one light anti-aircraft cruiser. The combined force included 386 aircraft: 193 F6F Hellcat fighters, 104 SBD-5 Dauntless dive-bombers, and 89 TBF Avenger torpedo bombers. The strike itself would consist of 249 aircraft, of which 158 were dive and torpedo bombers.

At 0600 on 4 December 1943, TF 50 commenced launch, with a 0750 time over target, Kwajalein Atoll. (Kwajalein Atoll is the largest in the world, roughly 100 nautical miles long and in some places over 30 nautical miles wide.) Strikes were planned at Roi, on the north side of the atoll, and Kwajalein Island, at the southeastern tip. In response, the Japanese launched about 50 fighters and a heavy triple-A barrage over target. The strike on Roi by Essex and Lexington aircraft was hampered by a communications snafu and effective Japanese ground camouflage. Only 12 Hellcats went in to strafe and managed to destroy just three Japanese bombers and 16 fighters on the ground, leaving 30 to 40 Japanese aircraft undamaged. However, 18 Japanese fighters and 10 bombers were shot down. In the meantime, 41 SBD dive bombers and 36 TBF torpedo bombers attacked the old Japanese light cruiser Isuzu and several other small ships. Isuzu dodged almost all the bombs and torpedoes. Only two bombs hit the ship, jamming her rudder but not sinking her. Several torpedoes hit the largest Japanese transport at Roi, the destroyer Asakaze Maru, which blew up in a spectacular explosion.

Concurrent with the attack at Roi, aircraft from Enterprise and Yorktown attacked the island of Kwajalein, which was the principle Japanese naval and submarine base on the atoll, with about 30 vessels in the lagoon. Three Japanese supply ships were sunk, and the light cruiser Nagara was damaged. At the seaplane base at Ebeye Island, 18 float-planes were destroyed. All told, the raids on Roi and Kwajalein cost the Japanese about 55 planes, whereas the U.S. lost five. Most of the Japanese merchant ships; all naval vessels and 30 to 40 bombers escaped destruction. Naval historian Samuel Eliot Morison noted somewhat acerbically that “the ‘Big E’ (Enterprise) had done relatively better when Admiral Halsey directed the first strike on Kwajalein, 1 February 1942.”

At this point, Rear Admiral Pownall made a controversial decision (one that would cost him his job.)  Although the plan called for a second wave of strikes to be launched at noon, and the senior aviators in the Task Force strongly advocated launching more strikes to take out the remaining Japanese aircraft, Pownall opted for caution and decided to withdraw, concerned that with the Japanese now fully alerted to their presence, the surviving Japanese aircraft represented a very serious threat. Up to this point in the war, U.S. carrier doctrine had been based on “hit and run” tactics. Staying put and duking it out with an alerted land-based air threat was generally considered a bad idea. Nevertheless, Pownall found himself on the wrong side of the cusp of a paradigm shift. In the History of U.S. Naval Operations in WWII, Morison treated Pownall’s cautious decision with much more kindness and understanding than did Nimitz or CNO King. Morison also noted that unlike Rear Admiral Arthur Radford’s Task Group (see also H-Gram 025), Pownall had no night intercept capability, and if he did not withdraw when he did, he could expect to face significant risk of night torpedo attack by Japanese bombers. (As it turned out, he faced it anyway.)

The Japanese tried hard to make Pownall’s fears become reality. Between 1000 and 1100, three Japanese Kate torpedo bombers from Roi or Maloelap attacked the carrier Lexington. All three got through the fighter defenses but were hit by anti-aircraft fire from the Lexington, crashing close aboard with one torpedo passing only 100 yards astern of the carrier. At 1248, as Yorktown was launching a strike on Wotje Island (in the southern Marshalls) four more Kates successfully avoided radar detection and fighter intercept and attacked Yorktown; three of the Kates were shot down by escorts and one turned away.

Pownall’s attempt to withdraw at high speed was thwarted by rough seas, forcing him to slow from 25 to 18 knots. As a result, the U.S. force remained in range of Japanese aircraft, and during the course of the evening somewhere between 30 and 50 Japanese bombers in at least 14 distinct raids attempted night torpedo attacks, all thwarted by maneuver and opening distance until finally, at 2333, one Japanese plane hit Lexington in the stern with a torpedo, killing nine men, wounding 35, destroying her steering engine, and jamming the rudder hard left. Through superb damage control, the crew was able to center the rudder, which enabled the carrier to steer with her engines, all while fighting off more air attacks. Despite the Japanese attacks, the remainder of TF 50 withdrew unscathed.

Pownall, however, did not escape unscathed. The commander of Pacific Fleet Air Forces, Vice Admiral John H. Towers, pushed to have Pownall relieved for being insufficiently aggressive. His view, and that of other aviators (Pownall was an aviator too) was that the best way to defend the carriers was to attack the Japanese bombers at their base. Yet it wasn’t so clear-cut. The bombers that attacked TF 50 at night staged through Nauru Island and might well not have been caught on the ground in a second attack on Roi. That Towers coveted Pownall’s job himself, a well-known fact, made the whole thing a bit unseemly. Nevertheless, Nimitz and CNO King also viewed Pownall’s action as insufficiently aggressive.

As it turned out, Pownall got Towers’ job, and Towers was bumped up to Deputy Commander in Chief Pacific Fleet. Vice Admiral Marc “Pete” Mitscher was appointed to command the Fast Carrier Task Force (which would be designated TF 58) instead. Mitscher’s selection by King and Nimitz to command TF 58 was somewhat to the consternation of Vice Admiral Spruance, the Fifth Fleet Commander, who was not consulted. The relationship between Spruance and Mitscher after the Battle of Midway was characterized by a degree of mistrust. Nevertheless, both of them got over it and went on to be very effective in battles that followed.

Having stripped Vice Admiral Halsey, Commander of Third Fleet and U.S. Naval forces in the final stages of the Solomon Islands campaign (see also H-Gram 024) of his battleships and heavy cruisers for the higher priority Gilbert operations, Nimitz decided to send some of them back, at least temporarily. While heading from the Gilberts to the Solomon Islands, a Task Group under the command of Rear Admiral Willis Lee (victor of the night battle off Guadalcanal on 14–15 November 1942) bombed and bombarded Nauru Island. The carrier Bunker Hill (CV-17) and light carrier Monterey (CV-26), with future President Gerald Ford on board, dropped 51 tons of bombs on the island, while the six new battleships––Washington (BB-56), North Carolina (BB-55), Indiana (BB-58), Massachusetts (BB-59), South Dakota (BB-57), Alabama (BB-60)–– hit the island with 810 16-inch and 3,400 5-inch rounds from a range of only 1,500 yards. Fifty-four 16-inch guns being fired would have made a great photo, but there doesn’t appear to be any, unfortunately. Also, unfortunately, the planes that had attacked Pownall’s carriers were already gone.  The destroyer Boyd (DD-544), while successfully rescuing the crew of a downed U.S. aircraft, was hit in the engine room and stack by Japanese shore battery fire, killing 12 men total, including everyone in the boiler room. About eight to ten Japanese aircraft were destroyed for a loss of four U.S. aircraft.

The invasion of the Marshall Islands would prove to be one of Admiral Nimitz’s biggest tests of leadership, as the heavy losses at Tarawa and Makin injected a heavy dose of caution into U.S. commanders and planners for the operation, similar to that demonstrated by Rear Admiral Pownall. The major question revolved around which atolls in the Marshalls to take first; whether to take the more audacious course and invade Kwajalein directly, or take one or more of the islands in the southern Marshalls first, as stepping stones. There were several possibilities in the southern Marshalls to include Wotje, Maloelap, Mili, or Jaluit, all of which had airfields and were heavily defended, as was Kwajalein itself.

Nimitz’s planners advocated taking one of the southern islands first. Vice Admiral Spruance, Rear Admiral Turner, and Marine Major General Holland M. “Howling Mad” Smith, all argued in favor of taking Wotje and Maloelap first. (Smith would later argue that Tarawa should have been skipped in favor of going directly to Kwajalein, but by mid-December 1943 he was in line with Spruance and Turner.)  Nimitz heard out all the arguments, and at the decision brief on 14 December, he announced that the U.S. would go directly to Kwajalein and bypass the southern Marshall Islands, which would necessitate neutralizing their airfields from the air. Spruance, Turner and Smith pushed back on Nimitz, but he would not budge. After the meeting was over, Spruance and Turner stayed behind and continued to press their case that going directly to Kwajalein was “dangerous and reckless” to the point that Nimitz finally told them that if they didn’t want to do it, he would find someone else who would. Nimitz’s specific rationale for defying his own staff and senior commanders is not clear. It is likely that after witnessing firsthand the results of the Tarawa assault, he reasoned that taking any island in the Marshalls was going to be a bloody affair, so better to take the one we really wanted and needed than take several just to play it “safe” at what would prove likely to be a high additional cost.

Under the plan approved by Nimitz, the U.S. would first take the essentially undefended atoll of Majuro, which had a magnificent lagoon (but no airfield), and which would serve as a base and logistics (and rest and relaxation) hub for numerous strikes by the Fast Carrier Task Force over the next months, until the capture of Ulithi in late 1944. While Majuro was being secured, the U.S. carriers would pound the other Japanese-occupied islands in the Marshalls before assaulting both ends of Kwajalein simultaneously. (The principal air base was at Roi-Namur to the north, and the principal naval submarine base and nearby seaplane base were at Kwajalein to the south. Roi-Namur and Kwajalein Islands are about 45 miles apart.)  Of note, although there are many atolls and islands in the central Pacific, very few of them were suitable for airfields, which had to be large enough, flat enough, and oriented to the prevailing east-west winds. It was these relatively few islands that the Japanese occupied and that the U.S. and Japan fought over (or bypassed).

The problem with attacking Kwajalein at both ends at once was that it would require two divisions of troops, and there were not enough assault transports to carry them. This resulted in a series of delays, from 1 to 17 and then 31 January 1944, giving the Japanese more time to improve their defenses on Roi-Namur and Kwajalein and to make more progress on a bomber airfield on Kwajalein. However, the Japanese were busy wasting their time trying to improve the defenses of islands the U.S. had no intention of invading. What the Japanese forces in the Marshalls didn’t know was that they were pretty much on their own, as the Japanese high command had already given up on trying to defend the outer ring of islands–the Gilberts, Marshalls, Solomons, and even the eastern Carolines, including Truk––and were focusing their defensive effort on another ring of islands––the Marianas, western Carolines (Yap, Palau, Peleliu) and the western end of New Guinea. The Japanese in the Marshalls shifted some troops to reinforce the southern islands of Wotje and Maloelap in the incorrect assumption that the U.S. would attack there first. This still left 9,000 Japanese defenders on Kwajalein Atoll.  

Kwajalein Operation, January-February 1944.
Namur Island, Kwajalein Atoll, photographed from a U.S. aircraft on 30 January 1944, before it was wrecked by pre-invasion bombardment. Note the many buildings and the pier (with a "hammerhead" crane) of the Japanese base there. Roi Island is in the far upper left. Virtually everything seen here was destroyed in the next few days (80-G-213594).

Operation Flintlock

The overall commander of Operation Flintlock was Admiral Nimitz, Commander-in-Chief of the U.S. Pacific Fleet, at his headquarters in Pearl Harbor. The operation would be executed by Vice Admiral Raymond A. Spruance, Commander of the Fifth Fleet, embarked on the heavy cruiser Indianapolis (CA-35.)  Rear Admiral Richmond K. Turner would command TF 51, the Joint Expeditionary Force, embarked on Rocky Mount (AGC-3) with the Commander Expeditionary Troops, Marine Major General H. M. “Howling Mad” Smith. Rocky Mount was a new type of specially configured amphibious command, control, and communications ship, based on what Rear Admiral Hewitt had improvised Ancon (AP-66) at the Salerno landings in Italy in September 1943 (see also H-Gram 021).

The joint expeditionary force (TF 51) included 297 ships (not counting carrier task forces or submarines) and 54,000 Marine and Army assault troops. TF 52, commanded by Rear Admiral Turner, was designated the Southern Attack Force, which would land the U.S. Army 7th Infantry Division on the island of Kwajalein at the southern end of Kwajalein Atoll. TF 53 was under the command of Rear Admiral Richard L. Conolly, embarked on Appalachian (AGC-1, sister ship of Rocky Mount) would land Major General Harry Schmidt’s 4th Marine Division on the islands of Roi and Namur (joined by a sand spit and a causeway) at the northern end of Kwajalein Atoll. TG 51.1, with the 22nd Marine Regiment embarked and under the command of Captain D.W. Loomis, USN, was the designated reserve force.

The Southern Attack Group was supported by the old battleships New Mexico (BB-40), Mississippi (BB- 41), Idaho (BB-42), and Pennsylvania (BB-38), heavy cruisers, light cruisers, destroyers, and the escort carriers Manila Bay (CVE-61), Coral Sea (CVE-57), and Corregidor (CVE-58). The Northern Attack Group was supported by the old battleships Tennessee (BB-43), Colorado (BB-45), and Maryland (BB-46); heavy cruisers, including Spruance’s flagship Indianapolis (CA-35); light cruisers, destroyers, and the escort carriers Sangamon (CVE-26), Suwanee (CVE-27), and Chenango (CVE-28).

Within the assault forces were multiple new types and modifications to amphibious craft, many incorporated with extraordinary rapidity based on Tarawa lessons learned. These included 24 new Landing Craft Infantry (LCI) modified as gunboats with 40-mm, 20-mm, and .50-caliber canons and machine guns, with some cannons configured to fire 72 rockets to impact just before the first troops hit the beach. The LVT amphibious tractors used at Tarawa had been replaced by a new and significantly modified type, the LVT-A1, which had been configured to provide close-in machine gun fire support, and the more numerous LVT-A2, configured to carry troops (and with the term amphtrac usually shortened to amtrac, “alligator” or “gator”).

Supporting Operation Flintlock was TF 58, the Fast Carrier Force, under the command of Rear Admiral Marc. A. “Pete” Mitscher. His was an extremely powerful force of six fleet carriers, six light carriers, and more than 700 aircraft, divided into four task groups. TG 58.1, commanded by Rear Admiral John. W. Reeves, with 199 aircraft on the veteran Enterprise (CV-6), new Yorktown (CV-10), and Belleau Wood (CVL-24), as well as the new battleships Washington (BB-56), Massachusetts (BB-59), and Indiana (BB-58), with escorts. TG 58.2, commanded by Rear Admiral Alfred Montgomery, had Essex (CV-9), Intrepid (CV-11), and Cabot (CVL-28); 212 aircraft; and the new battleships South Dakota (BB-57), Alabama (BB-60), and North Carolina (BB-55); and escorts. TG 58.3, commanded by Rear Admiral Frederick C. Sherman, with Bunker Hill (CV-17), Monterey (CVL-26), and Cowpens (CVL-25), with 156 aircraft and the new, just-arrived battleships Iowa (BB-61) and New Jersey (BB-62), with escorts. TG 58.4, commanded by Rear Admiral Samuel P. Grinder, had the venerable Saratoga (CV-3), the new Princeton (CVL-23), and the new Langley (CVL-27); 139 aircraft; no battleships as such but rather the brand-new class of heavy cruisers Baltimore (CA-68) and Boston (CA-69); and escorts.

Rear Admiral John H. Hoover was in command of land-based planes and was embarked on seaplane tender Curtiss (AV-4) at Tarawa. This force included more than 350 combat planes based at or staging through the airfield Tarawa (re-named “Mullinnix Field” after Rear Admiral Henry Mullinnix, lost aboard the escort carrier Liscome Bay, CVE-56) and new fields on Makin and Abemama Islands (the original “O’Hare Field”) in the Gilberts. B-24s staged through Tarawa for strikes on the Marshalls, while on Tarawa sat 44 Navy fighters for defense, seven Catalina seaplanes, and 49 bombers. These planes conducted extensive aerial reconnaissance of the Marshall Islands, in conjunction with extensive submarine reconnaissance. Vice Admiral Charles Lockwood, commander of submarine forces in the Pacific, also assigned six submarines to cover possible Japanese lines of approach; three submarines covered the major Japanese base at Truk, and one each covered the islands of Kusaie and Ponape in the eastern Carolines and Eniwetok at the far western end of the Marshalls.

Mitscher’s Fast Carrier Force began working over Japanese airfields in the Marshalls beginning on 27 January 1943. Armed with detailed photo intelligence and precise strike plans, these strikes were far more effective than those of 4 December 1943. As of 27 January 1943, the Japanese had about 150 operational aircraft in the Marshalls. By D-day on 31 January, there were none. The last Japanese fighter seen in the air over Kwajalein had been shot down on 29 January. The strikes also sank or damaged virtually all the Japanese shipping still in the lagoon. (All major Japanese warships had departed.)  The power of TF 58 had been so overwhelming that not one U.S. naval vessel would be attacked by Japanese aircraft during the entire Marshall operation.

TF 58 flew more than 6,200 sorties during the operation, 4,021 of them over target. U.S. air losses were 17 Hellcats and five Avengers to enemy fire, as well as 10 Hellcats, 14 Avengers and three dive bombers to operational accidents, with a total loss of 24 pilots and 24 aircrewmen. The attacks on Kwajalein would also be the debut of fighter planes armed with forward-firing rockets, which would be used in a ground attack (and later anti-ship) role.  Even the big four-engine PB2Y-3 Coronado seaplanes based at Midway got in the act, flying four-night bombing missions against Japanese-held Wake Island (which was within Japanese bomber range of Kwajalein) between 30 January and 9 February 1943.

Japanese submarines in the area fared no better than their aircraft. Of four Japanese Sixth Fleet submarines in the Marshalls, all four were sunk. Exactly which submarines were sunk by which ships remains unclear. Walker (DD-517) sank a submarine, probably RO-39, on 1 Feb with a single depth charge attack. (Accounts in Morison and at match on this. Some Japanese sources differ.)

On the night of 4–5 February, battleship New Jersey radar detected a submarine at a range of 21 nautical miles. Destroyer Charette (DD-581) and destroyer escort Fair (DE-35) were dispatched to investigate. Charette dropped depth charges on sonar contact and then Fair fired a forward Hedgehog pattern, which sank the submarine. (This would be the first Japanese submarine to be sunk by the Hedgehog weapon, which could fire a pattern of depth charges forward or abeam, rather than rolling the depth charges off the stern, the traditional way.)  Morison identified this submarine as I-21, but Japanese sources indicate I-21 was sunk by aircraft from escort carrier Chenango (CVE-28) in November 1943. identifies the submarine sunk by Charette and Fair as I-175, the submarine that sank the Liscome Bay (CVE-56) off Makin Island in November 1943.

All sources seem to agree that RO-40 was sunk on 15 February near Kwajalein by the combined attacks of the destroyers Phelps (DD-360) and MacDonough (DD-351) and minesweeper Sage (AM-111). Morison also credits Nicholas (DD-449) with sinking Japanese submarine I-11 on 17 February. At the time, Nicholas was only given credit for a “probable,” and Japanese sources suggest I-11 was sunk by a mine in the same period on a mission to the Ellis Islands (staging area for the assaults on Tarawa and the Marshalls). Others suggest this was actually I-175. Still other sources confuse the issue even more by giving credit to Nicholson (DD-442), which does not appear to have arrived in the area at that time. I’m not going to be able to solve this mash up, but the bottom line is that of the Japanese submarines sent to defend the Marshalls, none returned. The combined loss was more than 350 men.

The capture of Majuro Atoll on 31 January proceeded without a hitch. The three Japanese defenders actually surrendered. Majuro would serve as an advance logistics base, which would include the largest fleet of U.S. tankers (more than 14) assembled to date. The use of Majuro obviated the need for most refueling at sea while underway during the Marshall operations. Majuro would technically be the first Japanese territory (in Japanese control before the start of the war) to fall to U.S. forces during World War II.

Kwajalein Operation, January-February 1944.
Marines from the 4th Marine Division coming ashore under fire on Namur Island, Kwajalein Atoll, 1 February 1944. They are debarking from a LVT(2) amphibious tractor. In background is the collapsed "hammerhead" crane at the end of Namur's pier (80-G-213442).

On 31 January 1944, the Northern Attack Force commenced landing elements of the 4th Marine Division on Roi-Namur, with the initial landings intended to capture two small islands to secure the passes into the lagoon nearby. Based on intelligence, Rear Admiral Turner had determined that Roi-Namur would be a tougher target than Betio was at Tarawa. In many respects, he was correct. However, the Japanese were not expecting the landing to come from inside the lagoon and had arrayed their defenses to defend against an assault from the seaward side. Three days of air and battleship bombardment had destroyed all 83 of the Japanese aircraft on Roi as well as many fortifications. Battleships firing from only a mile off the beach poured 6,000 tons of shells onto the islands, compared to 2,400 at Tarawa. The seizure of the small islands flanking the entrances to the lagoon was hampered by rough seas, but the objectives were accomplished by the end of the first day. U.S. artillery emplaced on the islands along with LCI gunboats continued firing on Japanese positions during the night.

At 0100 on 1 February 1944 three U.S. destroyers opened rapid fire to cover a beach reconnaissance by navy raiders in rubber boats launched from the destroyer-transport Schley (APD-14). This reconnaissance confirmed that the lagoon-side beaches were suitable for landing and that there would be no repeat of the Tarawa tide/reef complications. By this time, battleship bombardment had killed many defenders, but it was lifted long enough for a daybreak reconnaissance by underwater demolition teams (UDT) under the command of Lieutenant Commander John T. Koehler, the first such use of UDTs (a lesson from Tarawa) for last minute check and clearance of beach obstacles. The two drone boats used by UDTs ran amok, but the mission was otherwise successful. The arrival of the LSTs into the lagoon, however, was accompanied by much confusion, which took time to sort out. Nevertheless, by 1157 the first wave of Marines hit the beaches, assisted by accurate close-in gunfire support by the Johnston (DD-557) under the command of Lieutenant Commander Ernest Evans. (Evans and Johnston would achieve lasting fame at the Battle off Samar in October 1944, but Evans established an early reputation for taking his ship closer to the beach than any other destroyer in support of Marines.)  At 1245 a huge Japanese ammunition dump on Namur exploded and debris raining down was responsible for killing 20 Marines. Tough fighting ensued, but by 1418 on 2 February, Roi-Namur was secured.

The Southern Attack Force commenced its attack on the island of Kwajalein and nearby islands at the southern end of Kwajalein Atoll on 30 January 1944 when the battleship Washington bombarded one of the islands flanking a key passage into the lagoon. Other ships bombarded the islands over the next day. Although the passes were assumed to be defended, which is why the small islands flanking them had to be taken as a precursor to the landings, as at Roi-Namur, the Japanese did not anticipate that the assault would come from the lagoon side, nor did they anticipate that the LVTs would be able to cross the reefs. The flanking islets did not in fact have artillery, nor were the passes mined or obstructed. In addition, Kwajalein Island was so narrow that there was no opportunity for the Japanese to conduct a defense in depth.

The initial U.S. Army preliminary landings went reasonably well, although in one instance troops were landed on the wrong island. On the plus side, however, the troops that landed on the wrong island also went aboard a beached Japanese vessel and found a trove of 75 secret charts of lagoons and harbors across the Pacific, which proved extremely valuable intelligence for future operations. By 1 February, the appropriate islets had all been secured.  

Heavy battleship bombardment of Kwajalein continued over several days. The new battleships Massachusetts, Indiana, and Washington bombarded the island on 30 and 31 January Pennsylvania, Mississippi, New Mexico, Idaho, and three heavy cruisers took over. At 0618 on 1 February the battleships resumed firing and the destroyers Ringgold (DD-500) and Sigsbee (DD-502) entered the lagoon and covered the arrival of the amphibious ships and craft. (Ringgold had done the same at Tarawa, after nearly sinking the U.S. submarine Nautilus (SS-168), and been hit by two Japanese dud rounds. She and Sigsbee were unscathed.) This time, unlike at Tarawa, the amphibious assault and supporting fires were executed so well that within 12 minutes, 1,200 troops of the U.S. Army 7th Infantry Division (veterans of the landings at Attu and Kiska in the Aleutians) were ashore without a single casualty, although after about two hours Japanese resistance began to stiffen considerably. Tough fighting continued on Kwajalein Island until 6 February.

By 7 February landings had been completed on 30 different islets around the Kwajalein lagoon without one U.S. ship being sunk and with only a few hits from Japanese shore batteries. The entire operation cost 372 soldiers and Marines killed (195 at Roi-Namur and 177 in the south).  Of 3,563 Japanese defenders on Roi-Namur only 91 were taken alive (40 of whom were Korean laborers), and in the south, of 5,112 Japanese defenders, only 174 were taken alive, including 125 Koreans. The hard lessons of Tarawa had been put into practice, and Admiral Nimitz’s insistence on going straight to Kwajalein was vindicated. The Japanese also learned the lesson that defending at the beach was a bad idea in the face of overwhelming U.S. Navy firepower. Instead, the Japanese began planning to defend from caves and tunnels in the interiors of islands, which would result in much higher U.S. casualties in future operations.

The Japanese also showed that despite their string of defeats, they were still capable of audacious action. At 0230 on 12 February 1944, six Japanese four-engine flying boats from Saipan, which had staged through Ponape, bombed Roi-Namur, hitting the U.S. supply dump and initiating a massive explosion that destroyed 80 percent of the ammunition, food, construction gear and other supplies on the island, killing 25 and wounding 130 men. None of the Japanese aircraft was shot down. However, no other Japanese forces were in a position to exploit this success.

(Sources for this section include Rear Admiral Samuel Eliot Morison’s History of U.S. Naval Operations in World War II, vol. VII, Aleutians, Gilberts and Marshalls. Also: The Admirals: Nimitz, Halsey, Leahy and King: The Five-Star Admirals Who Won the War at Sea, by Walter R. Borneman, 2012; The Fleet at Flood Tide: America at Total War in the Pacific, by James Hornfischer, 2016. Additional sources include Naval History and Heritage Command Dictionary of American Fighting Ships [DANFS] for U.S. ship histories and for Japanese ship histories.)

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Published: Fri May 03 15:53:40 EDT 2019