If there is no free will, it could be argued that the history of the universe really is "just one damn thing after another", and there is no such thing as causality.
For purposes of this post, assume that free will does not exist. Assume also that causality means that one event affects another more than other events; never mind temporal assymetry for now. If there is no free will, this means that only two kinds of events happen.
a) Random events that cannot be predicted individually, i.e., are not at all dependent on previous states (e.g., nuclear decays).
b) Macroscopic events which are dependent in the classical sense on previous events.
You might say that b's are always just (an apparently) special case of a's; we'll come back to that later.
Assuming a universe entirely of b's, entirely of clock-work macroscopic events - e.g. people appearing to choose actions, things falling, balls rolling when you kick them - in a fully pre-determined universe, which is essentially just a film running, it is incoherent to refer to any of these events causing another. We're just watching a movie, or seeing a frozen block of space-time moving by. Things could never have been otherwise, and the whole concept of counterfactuals becomes incoherent. To extend the film analogy - you might watch a film of someone kicking a ball, but the image of the person's foot did not cause the image of the ball to move. It was always going to move that way, right from the start. It's one damn thing after another.
Assuming that we live in a universe with both a's and b's, or that everything is an a and sometimes in large groups looks like a b (which is a better description of the universe we're in) doesn't get us out of hot water either. Now, we do have a degree of freedom, but since each event (nuclear decay or what have you) cannot be predicted, it's just noise. There's freedom but no relationship between events. It's still one damn thing after another.
You might object that the event that created the film (the actual objects we filmed and that determined what would go on the film; in analogy, the moment of the Big Bang) caused the image of the ball on the film to roll, but you can say that about everything in the film, and there's no sense in talking about causality being mediated through intervening events in the film. When the Big Bang happened one way but not another, that meant that I would write this blog post. Yes, along the way the solar system congealed from a debris disc in such and such a way, an allosaur ate one proto-primate and not another (that was my grandma), and various Mennonites moved from Switzerland to Pennsylvania at a certain time. But that was already set from the start, it's just that the film hadn't run to that point yet, and there's no sense in which something that happened ten minutes or ten years ago made me write this post any more than conditions at the Big Bang. In terms of special relationships between events, there is none.
This is not to be taken as a refutation of the "no free will" position, but rather to point out that this position contains a direct implication to most people's model of the world that I haven't seen discussed and which I think most no free will proponents would find problematic.
Modality is a bitch (updated)
10 hours ago