The subject of this work is a class of small United States Navy warships that were developed during World War II to combat specific threats from the Japanese in the Pacific Theater. As the war evolved, the nature, armament, and use for these ships changed to meet new needs in combat.
The conquest of most locations in the Pacific was the result of the actions of a Task Force or Task Group. The number of ships involved in these campaigns usually ran in the hundreds, sometimes over a thousand. In some instances in this work, it would almost seem as though the gunboats were the major factor in the conquest, but this is most certainly not the case. In a typical assault, battleships, cruisers, and destroyers provided heavy bombardment of the landing zone for one day to several days prior to landing day. As this was taking place minesweepers cleared the landing zone waters, with the gunboats following and detonating mines that had been cut loose. If the minesweepers came under fire from shore installations, the gunboats directed fire against them. Following minesweeping, the landing beaches were investigated by Marine reconnaissance units or Underwater Demolition Teams with the gunboats hovering closely offshore to suppress enemy fire directed against the swimmers. As the landings took place, the gunboats preceded the landing craft and then remained inshore for additional cover and call-fire support. In these roles the gunboats generally worked in concert with destroyers. If the firepower of the gunboat was insufficient, the individual boat might fire on the target from a closer range, identifying its position for the destroyer or other ship whose larger guns would then take the target under attack.
Some indication of the number of ships in a given operation may be deduced from the screening chores assigned to the gunboats after the initial landing. They patrolled around the anchorages, preventing attacks by suicide boats, suicide swimmers, and enemy aircraft. When not otherwise engaged they anchored or cruised upwind from anchored ships and provided smoke screens to cover them and thwart enemy air attacks. The variety of uses for the small combatants was large, and they were accomplished with great competence. They seemed to be everywhere at once. Their role was extremely important, particularly for the troops landing on the beaches that had enemy opposition. The presence of the gunboats only a few hundred yards off shore was comforting and added to their safety.
In the early stages of the war in the Pacific it was determined that additional fire support would be advantageous during island assaults. In addition, there was a need to interrupt Japanese inter-island barge traffic, as it had become an important means of transporting Japanese troops and supplies. In mid–1943 consideration was given to converting some of the existing LCI(L), or Landing Craft Infantry(Large), ships to gunboats. With their shallow draft they would be able to get in close to shore to support amphibious assaults and would also pack enough firepower to take on the armored Japanese barges. By the end of the war, 350 of the LCI(L) hulls mounted new and heavier firepower. Some, like the LCS(L), were built as gunboats from the start, while the LCI(G), LCI(R), and LCI(M) were converted from existing LCI(L)s.
The saga of the amphibious gunboats began with the attacks on the Treasury Islands in October 1943 and continued until after the war ended as they performed a variety of duties in the aftermath of the conflict. The early stages of the conflict saw the gunboat conversions put into combat against barge traffic and also to provide support for landings. As the war progressed and new varieties were developed, their tasks included anti–small craft patrol, the laying of smoke-screens, anti-aircraft assignments, and various patrol functions.
With the end of the war, most of the converted LCI gunboats were sent back to the states for scrapping. Some stayed on in the Pacific to aid in minesweeping and various duties in and around Japan, Korea, and China before being sent stateside. The LCS(L)s, built as gunboats from the start, survived to go on to service in various allied fleets, in France, Vietnam, and Japan, as well as other countries. By the 1980s most had been scrapped or sold off, with only one remaining in the Thai Navy. Today, that ship, LCS(L) 102, is the last remaining gunboat from World War II and is preserved as a floating museum by The USS Landing Craft Support Museum. Its present location is on the west coast of the United States.