"At that point in the war it was not necessary to do anything except blockade Japan. An island, dependent upon outside resources, Japan would have further withered. Wouldn't have been necessary to invade, either."

I wonder if Davin, Don, Lindy, or whoever would agree with your assessment?

While I'm here, let's try a simple question: "What terrorities did Japan hold in the time period you are talking about?
And in the context of WWII can you explain the concept called "island hopping"?
Bonus points for anything you can say regarding the "relationships" and activities between Russia and Japan during the time period you are talking about.

Now, let's assume that your "planned" blockade would actually result in Japan being "furthered withered". Do you have a guess about how many Japanese would need to die resulting from this blockade before Japan would surrender? How you calculate people dying resulting from the affects of "being withered" would "morally" equal the 1 person dying from bombs? Or does the fact that America sailors dying by the boatload from Kamikaze attacks "morally" somehow "equalize" those Japanese dying from the hardships of the blockade?
Finally, of course from the beginning of the war the Allies would done as much as possible to disrupt Japan's supply line [sink ships, etc]. Are you suggesting that some point formal annoucement that the Allies were going to put more effort into this, would be required?