From a personal perspective from here in the UK, 9/11 (to use the idiom of the place it happened, which is only fair, even if MM/DD/YYYY is an illogical date-system) was something that on the day was unbelievable, showed that no mainstream news provider on the web could cope with the demand for information, and really showed me when I got home that evening that when there's no news, a rolling news programme will just roll round and round and round on the same old piece of bald tire.
As for those involved, the majority of victims were quite obviously beyond help, so there could be nothing that could be said or done to make their situation better. I felt for the families of those lost or those relative few who were critical. I probably had my nastiest thoughts ever about what I would do if I ever came across whichever person was responsible (who would be OBL, but even if his name was being talked about on the day, I'm sure it wasn't certain enough that I knew that would be the person I'd be targetting) with I believe some thoughts about having that person strapped down to a table and to very thoroughly but carefully tap away with a small hammer to break all the bones I could. Like I said, nasty thoughts.
For myself, I was saying at the time that the near future was the kind of time that I would like to 'have lived through', without actually having to go through the whole living through process, given how unsettled everything was. As I'm now well into the stage of having lived through the whole episode (give or take the need to settle things down in the two countries arguably intervened in only because of the incident, but also one might arguably have been 'intervened' against anyway, if Bush had otherwise pulled back from his introspective form of foreign policy and decided he had something to do in that area), I'm not really sure it was worth all the hype my own interpretations of the tension at the time predicted about the years to come.
As to the US of A, at that point it had the sympathy and a good deal of support from the entire world (with a few minor and localised exceptions). Sympathy and support that, it has been pointed out by better satirists than I, it squandered away by become an aggressor instead of a nation merely exacting righteous retribution. (For the record, I don't think it was wrong to go in Afghanistan, nor to deal with Saddam in some way, although something in-between what happened and the way too cautious softly-softly approach now being applied to Libya, for fear of it being a third in the line of "Western Aggression" instances, would have been better from the start.) So, ironically, the 'rebellious' people of Libya may now be suffering because of the original fight against AQ.
Applying this to Japan: I can't do a thing about those who have died. I could do something about those who are alive (basically, anyone who is currently known to someone, as I don't think there'll be many people still to be found alive in either the earthquake rubble or tsunami flotsam), but that depends on personal finances. There is nobody I can consider responsible (I have no doubt that token members of the nuclear committee's management section will be hauled over the coals (fuel rods?) for safety failings, but honestly it was a nigh-on worst case scenario (barring a large asteroid landing in that part of the western Pacific) and there's this one location that's had a seriously bad situation dumped upon it, one other with more minor problems and several other locations where there's no problem.
I don't have the same "I want to have lived through this", mainly because Japan is just so remote that we're not going to have any direct or second-step-of-separation effects happening directly to me. I can't even see Welsh lamb being taken off the menu anywhere, again, because of the same problems with isotopes from the disaster having blown in over the country and being rained down into the mosses and grasses they're grazing upon.
Japan itself, has so far lived up to most of its existing stereotypical impressions, as far as this part of the world (and internet) is concerned. Although, even with the link to That Cartoon that I've just followed, so far I've not seen any tentacle porn circulating (although I anticipate it happening) based upon the details of this particular topic, so that's something yet to be seen. But aside from that, the attitude already compared in this thread to the archetypal British 'stiff upper lip', capable of dealing with disaster, seems to so far hold. From my perspective as someone perhaps more clued up in Japanese culture than the average person I might talk to in the street, and yet only casually so and certainly not a full-on japanophile with at least enough knowledge of kanjii to properly appreciate the likes of 2chan, the people of the nation of Japan appear at the moment to be dealing with their issues in the best way for their country, albeit in some circumstances by not making the individual fuss that would help the worst off to get the help they need.
Whether this continues is the question. Best case scenario, Japan rebuilds and if it weren't for the general cultural prohibition against breaking from the norm, there'd be proud wearers of "I survived the tusnami!" T-shirts, badges and baseball caps wandering around in a few years time. Most probably, there'll be a rough time. There will be a worse than necessary death-rate amongst survivors because of their stoic attitude towards the situation, compare with the situation in the Grave Of The Fireflies animation, prior to the main character braving the incendaries to loot. It could deteriorate to the extent that the incendiary/looting scene in GOTF also becomes relevent, which would sadden me. I cannot see any rhyme or reason for things to get to a Tunisian state of affairs (let alone the current Libyan one). Apart from there quite obviously not being a head of government who has ruled by force for so long (let alone the current emperor, who may have been around a significant while but is not the figurehead of force in any way, and is very much revered), the Japanese attitude and the north-African/Arab attitude might (if one can possibly generalise) be considered almost contrasting in all the relevant metrics.
And it is the generalising that matters. Not wanting to work in anything as apparently powerful as the fictional 'psychohistory' method of analysis, I'd still suggest that there's no apparent background swell apparent (as seen through this gaijin's overly round eyes, at least) that would so easily send Japan down that route, so I'd keep my Yen (albeit a little devalued) on the situation not heading that way purely from the triple-disaster (earthquake, tsunami and nuclear incident, but also respectively including the general humanitarian situations that arise from any or all of those three) we're currently discussing.
FWIW, MHO.