The fact that the "Christchurch Call" is vulnerable to being criticised as hot air is something for which we should be grateful. It suggests exactly the caution governments should apply to something as fundamental as regulating how we connect.
The worry after events like March 15 is the Reichstag fire effect.
In 1933, Marinus van der Lubbe, a lone-wolf Dutch communist, set fire to the German parliament. The newly appointed Chancellor, Adolf Hitler, immediately declared the fire the responsibility not of a single foreign terrorist but of the German far left.
He used it as a pretext to abolish a wide range of liberties, including secrecy of the post and telephone, free speech and freedom of the press. Like every aspiring despot, he knew these were the first essential steps towards absolute rule.
The Reichstag fire is the most extreme and cynical example, but the risk remains of overreacting to terrorist attacks and thereby granting the terrorist a win.
More recent is George W. Bush's reaction to 9/11, which killed a similar proportion of the population as March 15 did here. Osama bin Laden can surely only be celebrating in hell, given the chaos in the Middle East from the invasion of Iraq and the damage to US prestige, including from re-legitimising torture.
Jacinda Ardern's reaction to March 15 has been at the other end of the spectrum. There has been no declaration of war against Australia nor even condemnation of specific white supremacists. The Prime Minister refuses even to utter the lone terrorist's name let alone give publicity to his alleged cause.
Her gun reforms broadly brought the law into line with what most New Zealanders believed it was anyway.
The risk of overreaction by an NZ Labour-led Government was always more likely to be about free speech. It is only 12 years since Helen Clark cracked down on how we could communicate in election years after members of a religious minority published pamphlets critical of her policies.
Sure enough, Justice Minister Andrew Little mused soon after March 15 that current laws against hate speech aren't broad enough, suggesting more utterances should be criminalised.
The Green Party's human rights spokesperson, Golriz Ghahraman, wants to criminalise hate speech against religions, despite Parliament unanimously repealing blasphemous libel from the Crimes Act 10 days before March 15. Clark also seeks another crackdown on speech.
To her credit, the Prime Minister has said publicly that criticism of religious groups will not be banned and has indicated privately that her colleagues should be much less gung-ho. Little and Ghahraman appear to have got the message and dialled back their rhetoric.
The Christchurch Call involves an even narrower set of issues.
China and other authoritarian regimes are in practice excluded since the very first sentence requires signatories to support "a free, open and secure internet".
The diplomatic approach is more Apec's philosophy of concerted unilateralism than the WTO's binding rules-based system, with governments merely pledging publicly to do things they should be doing anyway, such as promoting media literacy among the young and enforcing existing laws against violent extremist content.
The Call respects that online services such as Facebook offer a spectrum of functionality.
At one end is when we message people one-on-one, analogous to the privacy of the post and telephone, and rightly left unaffected by the Call. If governments want to read our messages, they'll need a warrant.
At the other, is when social media users post or livestream content to the whole world. Recognising that social media companies should, like the Herald, voluntarily accept some responsibility as publishers is no attack on free speech.
More difficult is the line between the extremes. When does our Facebook or WhatsApp group get big enough that it moves from being analogous to a living-room chat, off-limits to the state without a warrant, to being more like a public meeting that government officials are entitled to attend?
More important than moves on livestreaming — which, after all, was the least of the terrible things that happened on March 15 — is the Call's commitment to change how social media algorithms direct us to ever-more extreme material.
These algorithms are why, when you sign up for your local fun run, social media content starts appearing suggesting an ultramarathon. Similarly, if you complain about immigration or join your local mosque, the same algorithms think you're interested in content from white supremacists or Islamist extremists.
It's not a violation of anyone's free speech for social media companies to respect that we just want to make it Round the Bays without giving our address to the organisers of Coast to Coast.
The Call also suggests social media companies will try to direct us to counterviews: by analogy an attempt to recreate the town square. When we start looking at Labour or Green material, the algorithms won't decide we should hear from the Communist Party, but more that we might want a peek at what National has to say.
It's undeniable the Christchurch Call is a diplomatic and political triumph for Ardern. Not since Jenny Shipley with Apec in 1999 has a New Zealand Prime Minister hosted any kind of international summit, and this one has exceeded expectations.
Nevertheless, we must be vigilant, especially with whatever Little and Ghahraman have in mind.
At this point, though, the Prime Minister has got the balance right, responding to legitimate issues made clearer by March 15 without undermining basic norms of an open, liberal democracy. She has not granted the terrorist a win.
• Matthew Hooton is managing director of PR and corporate affairs firm Exceltium.
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