In the relatively dreary world of Act II, Your Fault stands out as a reasonably entertaining moment, if not for the characters, then for the audience. The characters frantically run around accusing each other of being to blame for the giant's presence in a semi-patter song manner. Through the song, most of the characters of the show are variously assigned blame, whether dead or alive, whether or not able to defend themselves.
Here I will examine who is actually to blame for the needless loss of life in the show, not in terms of direct causality, but more in terms of to what extent their various actions are justifiable. Firstly, overcome by emotion, the baker looks to Jack as a scape goat. The Witch has already determined that this is the path of least resistance, as he is the one the giant wants, and his sacrifice can most easily solve their problem. Jack immediately denies blame on the basis that he couldn't have done anything without the baker's beans. With his life on the line, it is understandable that he would spit out any defence, but he doesn't win any points here by not taking responsibility for his own actions.
The baker defends the value of the beans, which is of course totally missing the point. Jack may still have decided to take the beans if he'd known they'd lead him to the sky, but in this assertation the baker is being just as dismissive of his responsibilities as Jack. Ironically, he then points this failing out in Jack, saying "Oh, and tell us who persuaded you to steal that gold." The baker then claims that anything he did was the witch's fault, as it was she who sent them on the quest to recover the cow. Here he almost has a point. It does seem unfair that the baker and his wife should have to go to all that trouble to become fertile, but life can be unfair sometimes, and just because it was caused by another, doesn't mean that anything you do to resolve it is justified. If he were thinking clearly, he would have remembered that this is his own, long held philosophy.
The witch blames the mysterious man for his indiscretion, but it was she who issued the punishment, based solely on her anger that the loss of her beans held a consequence for her, that the mysterious man could never had predicted. It was also presumably her choice to condition the lifting of the curse on obtaining what she needed to regain her beauty. For his own part, the mysterious man later admits that stealing the beans was foolish, but what of his wife? Does a pregnant woman have a license to demand things of her husband he can only obtain dishonestly? In fairness, I've never suffered a pregnant woman's cravings, but I think she has to take her share of the blame.
At this point, the discussion threatens to settle down, and would, if not for Jack's only moment of mental clarity. He points out that the giant must have come from a stalk grown from the bean that the baker kept. This is really getting off the point, as prevention of this possibility was never on any agenda at the time, but it does bring the blame to two parties it wouldn't have gotten to otherwise. Blaming Cinderella is ludicrous. She may have been a little self focussed throughout the ordeal, but she couldn't have been expected to have any affect on the outcome up to that point. Throwing away the bean was insensitive to the baker's wife at the worst.
The baker's wife herself may not be held culpable for losing the bean, but at this point I'd like to investigate her involvement in a way that wasn't brought up, either through ignorance or a desire by the characters to be respectful of the recently departed. I have no such desire when it comes to fictional characters, so I don't mind stepping on her grave a little (so to speak). Though fully aware of the importance of his mission, the baker starts out determined to acquire the necessary items in an ethical way. Admittedly, this doesn't last long, but this is mainly through the influence of his wife. She encourages him and gets him to struggle with his conscience, but she seems to have no such problem.
Cinderella diverts the focus back to Jack for continually going back to get more from the giant. First he states that he got the hen for his mother, which causes Little Red to chime in with some blame for her. This is a distortion of the truth. Jack's real reason for getting the hen was because he was under the impression that more gold would buy him back his cow, and he didn't want to go to his mother for more of the gold he'd already stolen. His mother may have been a little insensitive in always trying to get rid of Jack's best friend, but the real blame for this part of it lies with the baker and his wife. Jack was stupid enough to trade Milky-White for five beans, but when he asked if he could buy the cow back, the baker and his wife, while not knowing what was to become of the cow, gave him the impression that he could. If they had been honest with Jack at the start, he may never have ascended the beanstalk the second time. But then again he may never have sold the cow to them.
When Jack is confronted about the harp, he points out that Little Red dared him to get it. In this they both hold blame. Peer pressure is real enough, but again, it really comes down to Jack's need to take responsibility for his own actions. Finally, the group become united on a scapegoat: the witch. Just why was she keeping beans in her garden that would give giants access to their world?
Find this theme in other Sondheim songs: