Yes. It was not a war crime because it SAVED more lives than it cost. It was not a war crime because the Japanese refused to surrender and there's no use expending 1.2 million American lives when the loss of 200,000 Japanese ones will do the same thing. It was gruesome. Not a war crime.
What about:
US backing of chiles pinochet.
US backing of soeharto - more than 500,000 people killed
US in vietnam - 1 million vietnamese killed
US conquering of north america - 10 million people killed
US backing genocide of natives in south american countries
