No, the US faced those massive casualties in March of 1945 because the other 21000 buddies of these two were wiling to hold out. Must the entire population of Japan be exterminated through death from above and starvation below to make you bomb haters happy?
Ironically, the Hiroshima and Nagasaki bombings pretty much rendered the massive U.S. casualties on Iwo Jima in March 1945 — and later on Okinawa — a complete waste of lives on both sides. The B-29s that flew the bombing missions to Japan were stationed in Tinian, which is more than 1,200 miles southeast of Okinawa. The U.S. didn’t need those islands to win the war after all.
Japan would not starve AT ALL.
There farms were not and did not need to be bombed.
They were on rations because they were supplying their overseas ground forces.
If they had been blockaded, no food would have left Japan.