Should the United States apologize to Japan for dropping the atomic bomb?

No, I feel that doing so would open numerous doors for war crime and associated other issues, as an apology would indicate an unneeded/unnecessary wrong by the American people... It would be as bad as apologizing for saying "All lives matter" and carry with it similar repercussions on a much larger scale... We collectively decided, and took this step during a time of war knowing the outcome, and assumed the acceptable risks in doing so, so there is no need to apologize as right or wrong in this case is moot; unless we are now indicating that our actions were, indeed, wrong...
"Disclaimer" Most of you probably already know my feelings on the bombing of Nagasaki... If the US were to apologize for anything, I would agree it would be that bombing only.
I know this is contradictory to what I just wrote, but regardless right or "questionable", I will always back my Country over any others despite my feelings...

No because Japan was using a Total War concept.

Never. Have they apologized for the attack on Pearl Harbor?

Actually Japan has NEVER officially apologized for their war time atrocities. And not only no but H__L No!! We should not apologize for dropping the bombs. You do of course know that the Japanese Government was preparing to execute all POWs they held prior to the end of the war, Also they were gearing up to defend their homeland with military civilians etc. Bill Reilly's book on this subject is very good!!

Old timers in Japan are now contending that they tested a nuclear weapon off Korea. I doubt it but if true we needed to put an end to that.

I'm with those who say, No! WWII was total general war. The full resources of many nations were engaged in the fight. President Truman believed using nuclear weapons would save American and Allied lives. He was right. The US and our Allies won.

No.
America should apologize to Russia, China, Korea, and SEA for not bringing adequate justice on Japan. The atom bombs were nothing to them.
http://www.nytimes.com/1995/03/17/world/unmasking-horror-a-special-report-japan-confronting-gruesome-war-atrocity.html?pagewanted=all&src=pm

The first thing that came to my mind is Why should we? Are you aware that they don't discuss this and their atrocities in their schools. Did you ever been to any battlefield in the Pacific? I have just to name a few: Wake Island, Midway, Okinawa, Guam, the Philippines, and Mainland Japan, Hiroshima, Nagasaki, and yes Pearl Harbor and Kaneohe Bay, my home. I think that before we ask these kinds of questions we should consider the consequences of our asking the question. Again, "Why Should We Apologized for something that happened 77 years ago. Just leave well enough alone. Both Nations sacrificed a lot and we don't need to bring up the dead if we weren't there to begin with. Don't you agree?

Never

Wouldn't even think of it until after Japan has apologized for the Rape of Nanking, Luzon, the famine in Vietnam and every other crime they committed