Insurrectionary anarchism (IA) is a set of proposals having to do with achieving or approaching anarchy by means of informal organization and (supposedly permanent) conflict. These two principles are departures from anarcho-syndicalism (among others, but this most importantly) and its formal organizational structures and comfortability with negotiating with power.
IA may claim a tradition going back to Galleani and his milieu, as well as Stirner's distinction between revolution and insurrection, but emerges as a tendency through several Italian projects, with a heavy influence of the personality of Alfredo Bonanno. A favorite IA text (not by Bonanno, and enjoyed not only by IAs) is "At Daggers Drawn with the Existent, its Defenders and its False Critics". In English, Elephant Editions is notable for translating and publishing many IA texts. There is also Insurrection magazine from the UK, Killing King Abacus and A Murder of Crows from the US, and local publications such as War On Misery, that were strongly influenced by and/or sought to promote insurrectionary ideas.
More recently in North America IA has been confused and conflated with other streams of thought, including the Tiqqunist set of ideas (through for example the Institute for Experimental Freedom), class war/social war (through Vengeance and others), anti-civilization ideas, and even just a vague militancy or pro-violence activist anarchism. At this point, in most conversations I experience, IA is not talked about in terms of what it has meant, is supposed to mean, or its tradition, but instead as a code word for a pro-conflict stance or just coded way to say you are down, cool, or not the bad sort of anarchist. There is also a counter-tendency to try to set the record straight and return to the IA canon, which I can almost appreciate, but then I'm not sure it's possible or desirable to save something that, at least here, never got its legs under it in the first place, not to mention that such attempts will tend to come across as dogmatic.
How important IA, or its spirit, is for achieving anarchism is a matter of opinion that depends firstly on the assumption of anarchism as something to be achieved. You probably won't find many people on this site, or elsewhere for that matter, who see IA as The Way to Anarchy, but for many there are aspects--particularly attack and informality--that they see as crucial. For me IA is important for its having disrupted a particularly narrow way of thinking about anarchy (syndicalism) and, by shaking the anarchist space up a bit, encouraging thought along other lines, though IA is capable of turning into its own kind of narrowness and stifling imaginations. A friend said he appreciates IA's emphasis that you can start from anywhere, at any time. What it leaves less open is the question of what you can do from there.
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