In the handbooks of philosophy, you will see that like the epithet of a two-bit Homer, the adjective "vulgar" almost invariably attaches itself to the noun "materialism". Well yes! There is something trivial about reading the abject secret of a speculative permanence in the densest of social hierarchies. But that is how it is.Badiou, Theory of the Subject (p.185)
An excellent post by Infinite on the risks of a dialectics of nature and the rush to ontology (btw I don't have an ontology...). A rapid reply by Nick as well.
To add my meagre thoughts I'm not so concerned with deriving politics from philosophy / ontology / metaphysics, but rather with making a theoretically-informed political critique of philosophy etc. This is primarily because I regard it as perfectly possible to read a bad politics off SR / ANT whether they deny being political or not (allowing for the variants of SR). To be more particular, and this is elaborated at somewhat tedious length in my book, ANT is bad politics and bad metaphysics, precisely because the bad politics is derived from the bad metaphysics. Despite all the claims to make networks malleable and to regard capital as merely fragile network, these conceptions constitute a reformist voluntarism because of the fundamental desire to protect such networks from change and because they obscure, for me, the actual nature of the value-form.
I also doubt SR returns politics to its autonomy because, contra Nick, the tendency seems still to be to derive political consequences from metaphysics (see Graham's remarks about ethics and politics in the debate with Peter Hallward at 21st Century Materialism - vacuum-packed proletariat and all). Even if it does somehow make politics autonomous, we still have the problem of what SR adds then qua philosophy, which seems to be to return to certain 'traditional' questions (which is not bad in itself) but in ways that deny any connections with politics (which is bad). Finally, again, we have the possible political reading of SR precisely in this mode of detachment and refusal of politics. Perhaps a salutary dose of Lukacs is required.