Back in the summer of 1955, I was an 18-year-old sailor, serving aboard the USS Merrick, an attack cargo ship. In 1941, the total naval amphibious ships and the landing craft devoted to them was zero, yet by 1945 there was a D-Day invasion at the rate of a couple a month in the South Pacific. The Merrick was a product of the crucible of fire in the Asiatic Theater of World War II and our main battery. In other words, our reason to exist was the 24 landing craft carried on board. The guns, eight twin 20MMs, four twin …