As Martin Russ wrote in his book “Line of Departure : Tarawa”, “On the tiny island of Betio , the principal island of the Tarawa Atoll , the Japanese had constructed one of the most formidable fortresses in the history of warfare.” Rear Admiral Keiji Shibazaki, commander of Japanese forces on Betio, boasted, "it would take one million men one hundred years, to conquer the island.” 5600 marines of the 2nd Marine Division took the island in 76 hours, but not without paying a heavy