The U.S. has been waiting 14 years to move the Futenma Air base to a less crowded area. The belief is that corruption and hostility first allowed dense population growth around the air strip. And the same elements have delayed a solution. Mr. Gates' less than diplomatic demands on the new Hatoyama government reflect this frustration.
Unfortunately, it also reflects a belief by the Obama Administration that a DPJ government is: 1) so inexperienced that it must be lectured to like a child (and as a mother, I can assure you that that does not work) and 2) not going to be around long enough to matter, so it should get out of the way of the real business of statecraft.
The Obama Administration portrays the Futenma Agreement as a doomsday machine; if one component is tinkered with the whole system blows. This negotiating strategy may have seemed sensible back in 1990s when no political change was possible, but it sure doesn't play well today in a Japan that is seeking both on the left and the right to show some independence from the U.S.
Anyway, the best summary of Secretary Gates' talks in Tokyo can be found at Our Man in Abiko. He deftly translated the diplo-speak into real English; he was even kind enough to use American, not British English.