"When you got an all out prize fight, you wait until the fight is over, one guy is left standing and that's how you know who won." -Al Capone from The Untouchables.
Today is the 70th anniversary of the atomic bombing of Hiroshima. A few days later will see the 70th anniversary of the subsequent atomic bombing of Nagasaki. Each bombing immediately killed as many as 80,000 people in each city by most estimates. There would be many other people who would die later from wounds, radiation and cancers. The bombings finally convinced the Japanese Emperor Hirohito to drop most of his terms for surrender (over the vociferous objection of the military although like most so-called royalty being self-serving Hirohito requested to retain royal prerogatives). The other three conditions for surrender which the Emperor and the military leadership had previously insisted upon were (1) no military occupation of Japan (2) Japan would try its own war criminals (3) Japan would disarm itself. These conditions were obvious non-starters to the US though I would argue that the ensuing occupation was much easier than Japan had any reason to expect.
In any event the idea that one bomb could destroy one city made a huge impact at the time and obviously in the decades since then. There were some people at the time of the atomic bombings who thought that they were unnecessary if not criminal in nature. These weren't just people outside of the military either. Whether for moral or other reasons some leaders within the military and political establishment weren't sure that the use of the atomic bombs was justified. Others saw no problem with using the new weapon. Surely it was no different than the first person using a gun against an overconfident swordsman. If you're at war and have superior technology you use it. The Japanese surrender made a US invasion unnecessary and thus saved American lives. Before the atomic bombings, the Battle of Okinawa lasted almost 90 days and saw unbelievably vicious fighting and atrocities by both sides, including rape and deliberate targeting of civilians. The US lost around 14,000 marines and soldiers while the Japanese lost at least 77,000 troops. From this battle, both sides took the lesson that the invasion of Japan would be something close to an exterminationist undertaking. Now counterfactuals are always just that. No one can say for sure what would have happened. Some people have accepted the narrative that the atomic bombings were war crimes for which the US should be ashamed. Others say that we must work to rid the world of all nuclear weapons.
A very very very long time ago I used to think that the atom bombs were indeed criminal and likely racist in their application. But that was before I read Slaughterhouse-Five and researched the firebombing of Dresden. And later on (in my dissolute youth I was a WW2 buff) I learned all about the firebombing of Tokyo. More people died in the Tokyo bombing than died in Hiroshima. Does it really make a moral difference if someone is immediately turned to ash by a nuclear device or is incinerated or suffocated by a non-nuclear bomb? I don't see that it does. And certainly a nation that committed the Nanking Massacre has no room to point fingers about civilian casualties. The decision of moral import is whether or not to bomb a largely civilian area (though there were a high number of soldiers in Hiroshima). Once that decision has been made, everything else is just details. War, particularly total war, can and does often devolve to starkly utilitarian considerations. If you can break the enemy's morale and destroy his industry you can prevent well armed and supplied motivated soldiers from showing up at the front. If the enemy has no vehicles or communication or oil or gasoline then he can't effectively fight. More of his soldiers die or surrender and more of yours stay alive. That's the theory anyway. After the war it was discovered that aerial bombing of civilians had less of an strategic impact than many people had assumed. It just terrorized people and made them angrier. Nevertheless the bombings of Hiroshima and Nagasaki may have been the exception that proved the rule. Fear broke through the insane Japanese military code. Hirohito finally saw reason and surrendered, thus saving countless lives.
The atom bombs were horrible events. We should work to make nuclear weapons unthinkable. The US needs to stop its addiction to war and cease its arms exports. Everyone on this planet should work for peace whenever possible. But in 2015 the US has no reason to think of Hiroshima or Nagasaki as criminal actions. Japan started it; the US finished it.