Here is one Anarchist's critique of the G20 protests and the
aftermath.

The Politics of the Dispossessed.
I think that most people aren’t happy with the current situation in Australia. I don’t think there is any shortage of opposition to the Howard government, people aren’t getting active because they feel powerless against the forces of Globalisation and War. With over half a million (more like a million, more? I don’t know…) people coming out against Iraq, the government still took part in the invasion. I think that this struck a blow against people’s power. Such a massive show of opposition was amazing, but the government ignored it, demonstrating their contempt for the population. This seems to have had a demoralising effect on people and the Anti-war movement is much weaker today, then it was then. Why? In the face of Global Capital’s march to War, even mass action on a scale not seen since the Vietnam War had no effect. Despite efforts to keep the movement going, it had already hit its high water mark (so far).

Active Defiance as Propaganda.

The Arterial Bloc and friends took on the power of the State. Without weapons, they were able to demonstrate that you can actively defy the State and go pretty well. They didn’t manage to shut down the meeting, which would have been great, but demonstrated that even with a section of the City quarantined they would still be heard. The force of the State always exists whether it is confronted or not. The presence of horses and riot cops are designed to instil fear in the protestors, they are weapons of terror used daily as a threat against the people. The Police force, the Army, the “Intelligence” (sic) services exist as a force in potential, always ready to be used against the people. The Police exist to protect the rich from the poor, the powerful few from the ‘Great unwashed.’ The wild denunciations from the corporate media demonstrates just how concerned the government and corporations are, that their power has been so directly and successfully challenged.
I find it peculiar that many of the denunciations of the Arterial Bloc from the Left are from people who hold up Cuba as a Socialist Paradise. At G20 a few hundred unarmed protestors engaging in a bit of argy-bargy with the cops, they get denounced as “Ultra-Left”. At its low point, the 26th July movement in Cuba had 15 guys in the
Jungle with guns. How is one “Ultra Left” and the other not? Cuba, despite its Authoritarianism, lives as a shining example of what small, determined groups can achieve (I’m not arguing for some sort of Australian Guerrilla Army, but trying to demonstrate how small groups can affect change by being actively defiant of Authority).
From my experience, successful militant defiance tends to encourage others to engage in militant defiance too. People lose their fear of the State, start to see it as weak and beatable, not all powerful. They realise that they too can do something and begin to act.

Elitism

I have a different view of Elitism to the way it has been used in discussion. Hundreds of people acting together (even when masked up) is not Elitist. That’s militant direct action. Elitism is a handful of speakers (the Elite) preaching to the Spectators (who, by being there are already the Converted). The role of the audience is passive, just to make up the numbers. Putting on my Situationist hat for a moment, this does absolutely nothing to break down the Society of the Spectacle. People need to act consciously, they need to become aware of their own power, both as individuals and
together as a group. Not watching a bunch of Actors on a stage.  If I am going to travel a long way to attend a protest, I am going to do something. I am a free and conscious participant, not a passive receptacle for a bombardment of Socialist advertising.

A Diversity of Tactics
“Who can tell what’s right and wrong in this topsy turvy world?”-
Homer (Simpson).

 I doubt that disagreements over tactics will be resolved any time soon, if ever. No one group has a Monopoly on truth, which is why there are so many groups on the Left. Different groups come from quite different perspectives. I think that large protests containing the breadth of diversity that was on display at G20, should aim to facilitate the activity of the different groups. I see this diversity as a good thing. Different ideas about strategies and tactics can be carried out in the laboratory of the streets. Success and failure on display for all to see and learn from.
From past experience, I didn’t think that the Arterial Bloc and friends were that violent. The only injury sustained by a cop was a suspected broken wrist (in the words of my dad, who did he punch to get that?). What was different was the media’s response to the violence and the subsequent State repression. We might be used to ignoring the Spectacular presentation of protests as a false version of events, having been there we know what really happened, but many people still accept the corporate view of reality. I don’t really know how to deal with that, we are always going to be portrayed as the enemy by the corporate media and rightly so.
I think people are right to criticise the lack of communication from the Autonomous kids to the rest of the crowd. There was no effort made at all, I think this had a lot to do with the general disorganisation in the lead up to the protests. This is something that needs to be addressed in the future, by Autonomous kids themselves. Some of the difficulties are discussed below but the list is by no means complete.

Part of the problem with this is the different conceptions of democracy practiced by the Authoritarian and Libertarian Left. The Socialists expect a homogeneous, one size fits all mass protest. Any minority is expected to submit to the will of the majority. Libertarian democracy is founded on a respect for difference. I may not agree with what group X does, but they have to decide their own methods of protest, just as I am free to decide mine. I have found, from bitter experience, such diversity is not respected by the Authoritarian Left, the denunciations of the Arterial Bloc are a case in point. Faced with a situation where our right to decide for ourselves is not respected, communication becomes difficult because of the expectation that we’ll do what is decided at what ever meeting, regardless of whether that’s we intend to do or not. What’s the point of saying anything if we are just gonna get denounced anyway? If the situation was one where difference was respected this would not be a problem.
One of the main strengths of organising Autonomously is being able to adapt on the fly. People see what needs to be done and they do it. Sometimes this happens through the spokes-councils and other times it just happens. Everyone is free to act as they see fit.
This does lead to some difficulty in communicating to others what is intended because there is no one plan, and no-one in control. Things happen organically. Trying to force the protests into a passive, homogeneous mass is about control. If some organising committee tries to force protestors into a mould, that is an attempt to govern the protests.
Those on the committee become the “haves” (they have the power over the protests), those not on the committee become the “have-nots”, the passive spectators, the governed. I can’t really see the difference between accepting that form of organisation and accepting the decisions of the Australian Parliament, I choose to do neither. Like most Anarchists I refuse to be governed.

Overseas, Autonomous kids have organised locations at protests where Affinity Groups can formed and Autonomous politics can be discussed. (This is risky because this is how Agent Provocateurs can get in on the Spokes, I guess the risks/benefits have to be weighed up).
The Black Cat In A Hat.