This is the sort of post that blogs are basically made for: an intuitive argument that I believe is right but that I haven't dotted all the Ts and crossed all the Is yet. So, this is something I am putting out there to see if people think I should keep working at or if there are some obvious objections I am ignoring here.
This post makes use of a distinction between early Derrida and late Derrida. Such a distinction is, of course, obviously problematic and overly schematic. Simon Critchley, for example, categorically rejects such a distinction, stating that, "In my experience reading Derrida, the closer one looks, the harder it is to find any substantial difference between earlier and later work" (Critchley; Ethics, Politics, Subjectivity p. 96). My argument is not that there exists some clear demarcating line between early and late Derrida, or that elements of one doesn't exist in the other. But, I also believe that an ahistorical reading of an author, that doesn't take into accounts changes that occur during a thinker's long and productive career is a particularly good reading, either.
There are two elements that I feel are particularly worth paying attention into understanding a shift from an early Derrida to a late Derrida is (1) his relationship to Heidegger and (2) the centrality of resisting certain disavowals. These two points are not unrelated, but are held together through what Derrida called the question of the animal. As the question of the animal intensifies in Derrida's thought we see a continued distance being placed between Derrida and Heidegger, and so often and repeatedly over the question of the animal (from the 1968 The Ends of Man, to his 2001-2002 lectures The Sovereign and the Beast). And if we are to take Derrida at his word, that the most fundamental disavowal for him is the disavowal of the animal, then it should come as no surprise to us that his more political and ethical writings should become more central in his work at the same time that the question of the animal enters his work with a stronger and greater frequency. The argument here isn't just that you can't understand Derrida without understanding his work on animals, though that is part of my argument, it is also that you can't understand the specific shift of his work away from a strong heideggerianism and towards a strong political and ethical focus without understanding the way the question of the animals plays in the economy of Derrida's writing.