But just what is that somehow?

You write,

We Japanese are simply unable to spend any meaningful amount of time confronting Americans.

But if anyone was going to confront the Americans, it was Hatoyama. Something very concrete, very specific, must have been rubbed into his face to force such an ignominious reversal.  What could that have been?

I agree with Nomad:  It's a sad thing if the Japanese thought that closing the base entirely was simply not an option.

tuasfait - Japanese PM resigns

Mainstream media who believe in the alliance were appalled, and even rejoiced, at watching Hatoyama denied a tete-a-tete with Obama at the non-proliferation summit in Washington.

Really?  What percentage of the mainstream media wants Japan to continue being the USA's servile protectorate?  Most Japanese I know are disgusted with the status quo, with the American military still occupying prime territory all over the country.  How could there be such a disconnect between the media establishment and the general public?

The point is not to be right, but to get to right.