As always I have to thank Ellis for making very thoughtful and well specified arguments.

1. I don't think you can dismiss the strengthening of the alliance to just "some areas related to technological innovation." Those areas, such as Missile Defense in fact, whether the Japanese public realizes it or not, in some ways may very well lock Japan into the alliance and in fact into "collective defense." The technological interlocking of US and Japanese systems in BMD may well make it impossible for Japan not to help defend the US against a missile attack (I believe Chris Hughes has argued this).

I remember Chris Hughes making this point 11 years ago, and I certainly respect his work on missile defense.
Nonetheless, and Chris can chime in here if he disagrees, my sense is that the technological lock-in of Japan into US missile defense is something that looked likely 11 years ago, but has not materialized.
Japan retains effective national control over its Aegis based and Patriot PAC III interceptors, and I don't see any indication that the US could fire any of these missiles on its own. Radars are a bit more
complicated: the US radar at Shariki is important for US national missile defense, and the US perhaps relies on Japan's indigenously developed state-of-the-art S/L band radar, so in terms of information sharing there could be something approaching a technological lock-in, although even there it is not necessarily clear, and information sharing is quite different from having no choice over firing ordinance.

That said I certainly agree with one part of Ellis'
claim about strong and growing interdependence: while the ways that Japan depends on the US for its security have long been well known the strong and growing US dependence upon Japan in terms of national security, missile defense being a prime example, is something that is little recognized, especially in Japan. The failure of Japanese elites to recognize the extent to which the US depends on it contributes to their shocking lack of self-confidence, and arguably weakens the alliance as a result. For example, had they been more aware of this dependence, they could have more self-confidently bargained with the US harder on perennial alliance irritants like Futenma, resolved these (they obviously are not yet) and produced a stronger and more stable alliance as a result.

"Further, the recent "Operation Tomodachi" was much appreciated by the Japanese public and I think has wound up increasing support for the alliance."

A Cabinet Office poll released in early December showed that the number of Japanese who have friendly feelings toward the US rose 2.1% this year to 82%. 2.1% increase is not a very significant change, although that's obviously in part because the rate was already very high to begin with (those who reported having unfriendly feelings toward the US fell 2.9% to 15.5%, again not a big change).

It's also not clear how much of an impact Operation Tomodachi is having on larger Japanese perceptions of the US. Yomiuri's annual poll on relations released in mid December found that while 94% of Japanese positively evaluated Tomodachi, for the second year in a row more Japanese evaluated relations with the US as bad rather than good (41% bad versus 35% good). Also, trust in the US declined from 52% to 47%, while distrust rose from 37% to 42%. (As Ellis and I have discussed in person, some Japanese politicians have found their constituents are perennially skeptical of the claim that the US would actually defend Japan in a war). However, a counter-factual analysis might show a greater impact from Tomodachi, as in its absence (and assuming no 3-11 quake) perceptions might have been even worse. Indeed, perceptions deteriorated after 2009, perhaps reflecting on US behavior during the Futenma dispute with Hatoyama; Tomodachi perhaps made up for some of this behavior.

On final point about the Yomiuri poll, it shows a big gap in US and Japanese perceptions of their
relationship: Japanese are far more negative while Americans are much more positive, although also inattentive. 52% of Americans said relations were good, versus a mere 8% who thought relations were bad.
While MOFA diplomats are undoubtedly patting themselves on the back for a job well done in public diplomacy toward the US, this represents a significant store of political capital that Japan could use to solve difficult problems like Futenma (see below).

"Finally, I certainly agree that what responses you get depends on what questions you ask and their phrasing.
But there have been, as Paul knows, polls over the years that merely ask how close you feel toward other countries, and the % has never gone below 70% feeling close or very close to the U.S. but the responses toward China have been more negative than positive since the Tienanmin incident in 1989. I know that this doesn't reflect fear of a military attack by China, but I think for both the political elites and the public that fear for the future --always unspoken for fear of provoking China--is always in the background."

Actually, according to the Cabinet Office, the number of Japanese who felt close to China still outnumbered those who did not after Tiananmen, and continued to do so until the mid 1990s when those who did not feel close briefly outnumbered those who did by a small margin for about 3 years around the time of China's last nuclear tests and the Taiwan Straits crisis.
Afterwards those with a feeling of affinity outnumbered those without until the start of the Koizumi administration when the number feeling no affinity sky-rocketed and those feeling affinity plummeted.
Moreover, this does not capture the full movement of the Japanese public's views of China: around 1980 approximately 80% of Japanese had feelings of affinity toward China while only around 15% did not. In other words, Japanese at that time had views of China that were as friendly as their views of the US are today.
Those feeling affinity thereafter continued to be consistently over 70% before Tiananmen, while those without such feelings never exceeded 25%. In other words, depending on the nature of the relationship there has been large variation in Japanese views of China over the past 30 years, which means that today's views are by no means set in stone or determined by war history.

It is also worth noting that as recently as 1995 (when unfriendly views outnumbered those feeling affinity to China), a Yomiuri poll found that more Japanese regarded the US as a military threat than so regarded China (26.6% viewed the US as a military threat versus only 21.3% who so viewed China). Similarly, several polls from the 1960s and 1970s found the US being identified by more Japanese as a potential military threat than was China. While I am not claiming that this result would be found today (I doubt it would), it again shows that the public's views of China and the US are more dynamic, overlapping, and less rigid than is often portrayed.

2. Koizumi's movements to regionalism I think are part of the consistent pattern of Japanese foreign policy in the last decade toward its "dual hedge," as Heginbotham and Samuels have called it, that is, of moving closer to Asia politically and economically to insure against becoming too dependent on the U.S. (its "satellite" in the terms we have discussed it here) but moving closer to the U.S. militarily to protect itself from the threat of China and the DPRK. Some refer to this as a "strategy," but I personally think that this is as much a reflection of Japan's place in international geo-politics and geo-economics as it is a strategy.

This is not an unreasonable way to look at Japan's policy or response to its situation (although no geopolitical situation entirely determines a nation's response). However, the dual hedge can also be a step toward Menon's proposed strategy of a multi-hedge for a Japan outside the alliance. Japan's new strategy of building ties with India and Australia also fits into an emerging multi-hedge strategy. Also, if Japan really saw China as a threat, like it does North Korea or did with the Soviet Union in the past, it would not trade with them for fear of building up a military threat, not to mention the dangers of becoming dependent.

"3. Speaking of Futenma, I think Paul and I would agree that the Okinawa bases are the soft "underbelly" of the US-Japan alliance: this is the issue that has the potential to undermine it more than any other (other than a conflict with China over Taiwan perhaps). I think we probably would also agree that the U.S. would be stupid (and may be even now) to think that Futenma was the end of this issue and now they could ignore it."

Yes, I strongly agree with Ellis on this.

"(Hatoyama had absolutely no leverage with the US on this issue whatsoever; it's a terribly incompetent politician who pushes an issue in a negotiation when he or she has no leverage with the other party!)."

"(Hatoyama had absolutely no leverage with the US on this issue whatsoever; it's a terribly incompetent politician who pushes an issue in a negotiation when he or she has no leverage with the other party!)."

I would absolutely agree that Hatoyama was a terribly incompetent politician, but that was because he was so unbelievably feckless. He could not keep a position for more than 5 minutes. Some of his many proposals were notably better for the US than the poorly conceived Nago base plan (e.g. the Katsuren peninsula proposal), but he totally lacked the fortitude to carry through. If he had shown a bit more perseverance and Gates and Clinton had actually noticed how bad the Nago deal was and that he was making a better offer, they would certainly have come around.

As for leverage, I have to disagree there: Japan had all the leverage it needed on the issue. If Japan had asked the US to remove the Futenma USMC air base from Japan the US would have had no choice, but to agree (consider Iraq, a far weaker power in a far worse position that was able to order out US troops, or the Philippines or Thailand that ordered out all bases).
As Richard Armitage reportedly said, the US would kick and scream if asked to remove Futenma, but in the end it would have no choice but to comply.

Paul Midford