I think that a view from a bridge the Sicilian Codes of conduct and honour are very important to the development of the play as they form an integral part of the plot. The split between the old world Sicilian Codes and the new world American vales is very evident as people form the same families being on different sides of the divide for example Catharine is warming to the new world values where she does what she wants to do but Eddie still believes strongly in the old world values and so tries to control her as he is head of the family, but Beatrice personally believes in the old world values but acknowledges Catherine's need to move to the new world values but Eddie will not allow her. This contributes to the development of the play by causing a greater amount of tension than just Rodolfo and Catherine have and creates a conflict of interest between Eddie and Catherine, because Eddie could not control her and Catherine did not think she should be controlled.
The community did not live by the law of America but their own law they all lived by the Sicilian Codes, which made Eddie, as the man of the house head of the family and so demands respect and obedience from the others in the family and is expected to protect them. Marco is in the same situation as Eddie as he is also the head of the family and is expected to look after Rodolfo so that when Eddie insults or threatens Rodolfo Marco has to stand up for him and get justice by the Sicilian Codes so that when Eddie kisses Rodolfo in an attempt to prove his homosexuality if they had told Marco he would have had to have killed Eddie even though at that point he had no personal problem with Eddie and even had respect for him.
In a view from a bridge I think that Alfieri acts as the view from a bridge allowing the audience to see more clearly the differences between the old and new world values as well as being a bridge between the audience and the characters and for the characters between the old and new world values. In some ways I think that Alfieri was a product of parents that believed strongly in the old world values as he himself was from an immigrant family, for example he is a lawyer so his parents must have given him a good schooling so show the value to want something better for your children than you have for yourself, he also shows the move between the old and new world values, meaning that he as a second generation immigrant has moved now to the new world values but still understands the old world values as Catherine and Rodolfo have.
Eddie originally has a problem with Rodolfo because he does not consider him a man and has skills like most men do not like cooking and dress making he is also blond with blue eyes which is very uncommon among the male immigrant population, this convinces Eddie that instead of having to admit to himself that the reason he does not like Rodolfo and Catherine being together is because he loves Catherine but it is because Rodolfo is gay and not right for her as he is not big and strong like him and Marco and so would not be able to look after Catherine as a husband should, this gives him more reasons not to face the truth and this leads to his eventual ultimate betrayal of all the old world values even though he still believes in them.
Eddie thinks that Rodolfo should be a man like Marco 'nobody kids Marco' so he gets respect from people like a man should but with Rodolfo 'they laugh at him behind my back.' Eddie takes this as them laughing at him because Rodolfo is a relative and so has to protect him so if they laughed at him in front of him he would have to do something about it like Marco has to, this affects the development of the play by enhancing Eddies view of him as more feminine or homosexual because he needs protection and so increases the thought that he is not right for Catherine.
Alfieri is also considered a man, as he is a successful lawyer so he can protect his family through money, this helps Eddie to be able to go to him for advice about things that he could only talk to man about because he could not discuss thing of that nature with his wife as it would be considered wrong, for example when talking to Alfieri he says 'I'm tellin ya Mr Alfieri the guy ain't right.' Eddie could not trouble Beatrice with this as it would be considered disgusting to talk to a woman about such things as they were not supposed to know about them. I think that Eddie not being able to open up to Beatrice could have stopped him sorting out the problem rationally as she would been able to offer much better support than Alfieri as she may have been able to do something to stop him.
The Sicilian Codes played a major part in the development of 'A view from a bridge'. They caused the development of almost all if not all of the problems experience by Eddie Carbone in the end of the play., for example if the Sicilian Codes had not made him take in his cousins he may not have done or if they had come at least they may not have stayed so long, also if the Sicilian Codes did not spell out what a man was supposed to do for his wife this may have caused less conflict between Eddie and Rodolfo as Eddie would have had less reasons for him not to be able to look after Catherine and may have been forced into submission, also if they had lived by American laws then he may not have accepted them in the first place. So if the Sicilian Codes had not been in place the whole episode may not have occurred, this shows that the Sicilian Codes were essential to the development of the play.