Derrida's not as popular as he once was, to put it mildly, but his early and mid career texts are still as sharp as they ever were. Zizek's got a recent piece to that effect in Critical Inquiry (here's the best copy I could find). "White Mythology," on the relation between philosophy and its employment of metaphor, is one of those essays that has enduring value.
Metaphors are useful for philosophy not so much when they are on the surface, protrusions that can be objected to and reformulated, as when they become ingrained into discourse as unavoidable. The metaphor for this metaphor is the coin that has circulated until the imprint has worn off and it is returned to bullion. Value then appears to be intrinsic to the thing (or figure) in itself rather than of human minting.
This brings us to the question of representation or mediation of animals in relating them to discourses not especially friendly to animals in themselves. As discussed in Scu's previous posts, Agamben's work provides one of the best starting points for fitting animals into a biopolitical schema but is basically a kind of human exceptionalism.
Relating "bare life" to one's lived experience--contextualizing it in the situation, to use Badiou's term loosely--asks for some kind of representational linkage. Animals are probably not mistaken for zoe because everyone misreads Agamben but because the abuse of animals reducing them to bare life has been accomplished as the metaphorical ellision of the metaphor. The statement "animals are like bare life" has become "animals are bare life" by repetition.
Animals are not in themselves (or as defined by Agamben) bare life: definite process reduce them to that condition. Materially animals are stripped of their particular way of life through the torture of the factory farm; in discourse they "become" (mistaken for) bare life through the insistence that this, the scene of torture, is where we find the real animal. When the image of the animal-as-bare-life becomes the dominant one through which animals are thought or enter into political consideration, the naturalization of animal abuse has succeeded. Paradoxically, the techniques for raising awareness of animals abuse can also ensure that they continue to stand for and in the zone of bare life.
The agony of the rat or the slaughter of a calf remains present in thought not through pity but as the zone of exchange between man and animal in which something of one passes into the other. - Deleuze and Guattari, What Is Philosophy?
