MacKinnon sometimes comes quite close to saying that the modern state is a sexist relic that has had its day. Surely, however, the state is the largest unit we know of so far that is decently accountable to people's voices, and thus it is bound to be of critical importance for women seeking to make their voices heard. I think there is also a moral argument for the state: It is a unit that expresses the human choice to live together under laws of one's own choosing. Once again, it is the largest unit we yet know that expresses this fundamental human aspiration.
From Marthan Nussbaum's excellent review of Catherine MacKinnon's book (also by all accounts excellent) Are Women Human?. Highly recommended.