The history of the specialist amphibious assault vessel really begins during World War II. Prior to World War I, amphibious assaults had taken place using conventional boats. The disastrous Gallipoli landings of 1915 showed that this type of operation was impossible in the face of modern weapons, especially the machine gun. The 1920s and 1930s did not see much progress in most of the world, the exception being by the United States Marine Corps. Small-scale operations conducted by the Marine Corps in Latin America in the 1920s and 1930s, known as the Banana Wars, led to the development of advanced amphibious assault doctrine. By the late 1930s, concrete plans were beginning to form to build the first true specialized amphibious assault ships.