Modern U.S. Navy Amphibious Assault Ships project power and maintain presence by serving as the cornerstone of the Amphibious Readiness Group (ARG) / Expeditionary Strike Group (ESG). LHA/LHD are a key element of the Seapower 21 doctrine pillars of Sea Strike and Sea Basing, transporting, launching, and landing elements of the Marine Expeditionary Brigade (MEB) via a combination of LCAC hovercraft, amphibious transports and vehicles, helicopters, and aircraft.
Designed to project power and maintain presence, LHA-Replacement (LHA-R, aka. LH-X, and now the New Amphibious Assault Ship or NAAS) large deck amphibious assault ships were slated to replace the US Navy’s 6 LHA-1 Tarawa Class vessels. They are based on the more modern LHD Wasp Class design, with the LHD’s landing craft and well deck removed in favor of more planes and hangar space. While its LHA/LHD predecessors were amphibious assault ships with a secondary aviation element, it’s fair to describe the America Class as escort carriers with a secondary amphibious assault role.