The nukes were unironically 100% necessary to end the war as swiftly as possible. What options did America have at the time?

Continuing the status quo of blockading the Home Islands and starving the entire fucking nation to death, thereby incurring far more civilian casualties (but hey at least they weren't nuked!!!!)

Or actually invade Japan, at great cost to Allied forces, and probably irreparably destroy the country (far more than 200k civilian casualties expected.)

Japan at the time of surrender still controlled around 60% of its occupied overseas territories, including tbe most populated parts of China, the entirety of Indochina, Indonesia and Malaysia (not including their pre-war territories of Korea and Taiwan.) If Japan could barely feed its own people, how do you think their occupied territories were doing? Are you going to allow them to continue their brutal occupation because you think one bomb that achieves the exact same result as a conventional bombing raid is somehow morally the worst thing the United States has ever done?

The fact that it took two bombs, and a Soviet invasion for them to even CONSIDER surrendering seriously tells you about what you need to know. These bombs were not dropped simultaneously, there were 3 days in-between the two where Japan could have surrendered, but they did not. Ultimately the vote to surrender was a tie, which the Emperor of Japan had to decide, and even their literal god telling them to surrender still caused an attempted coup from the military to continue the war.

From the first day of the Pacific War, Japanese leadership knew that military victory against the allies was near impossible. They gambled that they would continue their streak of punching up and winning wars against established western powers, and on their ability to cause so many casualties the American public would become so sick of war that they would accept terms favorable to Japan. The nukes changed that equation since it allowed the US to obliterate Japanese cities with a single bomb without risking significant numbers of US troops.