I wonder if USA had used chemical weapons, poison gas, like mustard gas and other choking agents, if battle would have been less costly for us. The poison gas would have been very effective at settling into their caves and tunnels unless they had good ventilation systems. We had enormous stockpiles of poison gas, we could have stood off the island and shelled with gas for a week or so, then wait for most of the gas to dissipate before going in with troops. I don’t think japan signed any of the agreements about usage of such weapons. They experimented with plague on our pow’s, they would have had no right to bitch about being gassed.