To me, 9/11 was in the same category as the 1991 Russian coup, in terms of imemdiately apparent historical significance. That makes two events in my lifetime. So, I guess once in a generation is about right, worldwide.

At the national level the rate is much lower, maybe once every 2-3 generations as you say.

guaranteed to evoke a violent reaction from police is to challenge their right to "define the situation." --- David Graeber citing Marc Cooper

To make an analogy is not to suggest things are exactly the same; I am, of course, aware that 9/11 had a far greater impact. The analogy was the general one of making criticisms of US foreign policy very soon after an attack on Americans, whatever the scale, which is going to get very negative responses from many Americans. I'm sure this will be used against Greenwald in future.

It's not true that Chomsky's response was "only" going to get a vicious response; some agreed with his point and others were provoked to think about it. But yes, there were many "vicious" responses. The first and negative comment on Greenwald's article was:

"TrueToo
16 April 2013 2:58pm

Isn't it a little soon to be exploiting this atrocity for your propaganda purposes, Greenwald?"

and it was recommended by 822 people so far.

But this was in the Guardian, so this response:

guichp
16 April 2013 3:12pm

@TrueToo - It's not propaganda,it's Ethics.Look it up sometimes.
Thank You Glenn.

got 932 recommendations.

This has so far got 651 recommendations:

Doggieinthewindow
16 April 2013 3:26pm

"... If there is anything obscene, it's people like you pretending they care about people they don't actually care about at all. If you had an ounce of real empathy for people you don't know, then you could not react as you have to this blog entry.

That you already have 30 recommends (now 822) for this masturbation is today's intellectual atrocity du jour."

So far there have been about 2,700 comments - I think that's a good thing that there is discussion about media coverage, attitudes to the killing done by US forces in other countries,  
possible further erosion of civil rights, etc.

I don't share your dismissive attitude and weary cynicism; I think it was well argued and very well researched for something written so soon after the event. Did you actually read it ? Maybe not, given that you only refer to the things in the brief extracts I quoted. I think that in a general review of media responses it was appropriate to cite that of the New York Post - along with a variety of other media and twitter responses (this includes a number of links):

The Post's insinuation of responsibility was also suggested on CNN by Former Bush Homeland Security Adviser Fran Townsend ("We know that there is one Saudi national who was wounded in the leg who is being spoken to"). Former Democratic Rep. Jane Harman went on CNN to grossly speculate that Muslim groups were behind the attack. Anti-Muslim bigots like Pam Geller predictably announced that this was "Jihad in America". Expressions of hatred for Muslims, and a desire to do violence, were then spewing forth all over Twitter (some particularly unscrupulous partisan Democrat types were identically suggesting with zero evidence that the attackers were right-wing extremists).

He also referred to Muslim reactions (with links again):

One continually encountered yesterday expressions of dread and fear from Arabs and Muslims around the world that the attacker would be either or both. That's because they know that all members of their religious or ethnic group will be blamed, or worse, if that turns out to be the case. That's true even though leading Muslim-American groups such as CAIR harshly condemned the attack (as they always do) and urged support for the victims, including blood donations.

 One tweeter, referencing the earthquake that hit Iran this morning, satirized this collective mindset by writing: "Please don't be a Muslim plate tectonic activity."

He also refers to the possible consequences for most Americans:

The history of these types of attacks over the last decade has been clear and consistent: they are exploited to obtain new government powers, increase state surveillance, and take away individual liberties. On NBC with Brian Williams last night, Tom Brokaw decreed that this will happen again and instructed us that we must meekly submit it to it:

"Everyone has to understand tonight that, beginning tomorrow morning early, there are going to be much tougher security considerations all across the country, and however exhausted we may be by that, we're going to have to learn to live with them ..."

Given the decline of serious journalism I'm happy to see well-researched, timely  and thoughtful articles like this - and the amount of response it gets. I don't agree with your caricature of it so I also don't agree with the pessimism of "Nothing changes". Nothing will change unless people do criticize the existing situation in the way he has and say things lots of people don't want to hear.

Of course I'm only slightly biased by his recent defense of Noam Chomsky :-) - which included criticism of some of the Guardian's coverage of him, and this:

But the strangest attack on Chomsky is the insinuation that he has changed nothing. Aside from the metrics demonstrating that he has more reach and influence than virtually any public intellectual in the world, some of which Edemariam cites, I'd say that there is no living political writer who has more radically changed how more people think in more parts of the world about political issues than he. If you accept the premise (as I do) that the key to political change is to convince people of pervasive injustice and the need to act, then it's virtually laughable to depict him as inconsequential. Washington power-brokers and their media courtiers do not discuss him, and he does not make frequent (or any) appearances on US cable news outlets, but outside of those narrow and insular corridors - meaning around the world - few if any political thinkers are as well-known, influential or admired (to its credit, the Guardian, like some US liberal outlets, does periodically publish Chomsky's essays).

http://www.guardian.co.uk/commentisfree/2013/mar/23/noam-chomsky-guardian-personality

Maybe it's because I'm a Londoner - that I moved to Nice.

That link doesn't work for me - but the chart referred to can be found here:

http://steffislee.files.wordpress.com/2013/04/arrest_large.jpg

From Greenwald's follow-up:

On Tuesday afternoon, CNN humiliated itself as badly as it ever has (which is saying quite a bit). The network's anchor John King, and its "terrorism expert", former Bush homeland security adviser Fran Townsend, both "reported" - as part of a "Breaking News" scoop that CNN loudly and excitedly trumpeted - that an arrest had been made in the Boston case and that the person was, as King put it, "a dark-skinned individual" (more or less simultaneously, Fox also reported the arrest). An hour later, it became clear that this was totally false. Raw Story details what happened here, and BuzzFeed (which one might at this point reasonably say is a level or so above CNN in the news reliability department) has the very amusing and appropriate mockery here.

But the best commentary on this debacle came from Chris Hayes' top-of-the-show seven-minute scathing monologue on MSNBC last night, where he not only crystallized why this was so journalistically reckless but, more importantly, explains exactly why CNN repeatedly said that the arrested person was "dark-skinned":

Townsend has built up quite a history at this point. It was she who visited Abu Ghraib in 2003 and put pressure on the prison officials there to extract more information. She then served as one of the paid shills for the then-designated terrorist group Mujaheddin-e Khalq (MeK), even as she used her perch at CNN to cheer for broad interpretations of the "material support for terrorism" statute that sent American Muslims to prison for decades for far less involvement with such groups than she had with the MeK. And now she's at the center of this reporting disaster. Good job, CNN: nobody could have guessed that a Bush terrorism official would produce outcomes like this.

http://www.guardian.co.uk/commentisfree/2013/apr/18/torture-report-cnn-terrorism-iran

Maybe it's because I'm a Londoner - that I moved to Nice.

No, it isn't very good metaphor, partly because it's another caricature of what he did, and also because it leaves out the pollution marketers sitting around the bed and trying to push their lethal products on the victim and any visiting relatives. Maybe you should have waited till you'd had a good sleep and considered the matter a little more seriously :-)

Did you read the article ? A lot of it is about the irresponsible media coverage which had ALREADY taken place - THEY had quickly jumped in to reinforce their agendas.

He also reports on and links to the already existing Muslim reaction and their understandable fears.

He's contributing to an already existing discussion - a time when some key issues are getting a lot of attention and it's important in THAT context that responsible, critical voices contribute. Are you seriously suggesting that he should leave it to the largely right-wing media to promote their views ? At such a time it is particularly important to contest such views and argue, as he does, against the likely further erosion of civil liberties.

Maybe it's because I'm a Londoner - that I moved to Nice.