World War Two: U.S. Military Plans for the Invasion of Japan are the formerly Top Secret records for the invasion of Japan, if the A-bomb didn't work or didn't meet military and/or production deadlines. These records show that invading Japan on the beached, in a Normandy-style invasion would have been an enormous blood-bath; estimates were that 250,00-1,000,000 lives wourld have been lost in attempting an invasion of Japan by Sea.