Bare this in mind.. The Japanese didn't surrender just to the nuke. The Americans flew most of their air power over toyko a few days after in show of strength, after that the Emperor said to the people that Surrender is better then death.
As for the nuke being dropped... i think it was needed as Japan provided the "testing" ground for it and it showed russia that the usa had the capability to destory cities with 1 bomb instead of a thousand, a hundred thousand, or a million bombs!
Do i think that this needs to be aruged? not particually, however its intresting to see the discussion