Some thoughts on a main motive of the show which is important in this episode:
All of our main team members were at one time in their life thrown into a situation of extreme loneliness: Finch after Nathan's death, John after he got betrayed by the CIA and learning about Jessica's death, same fate for Shaw after getting betrayed by Control and Cole's death and Root very early on when no one believed her after the kidnapping of her friend, she later run away from home and was on her own all her life. Nathan's little project of the irrelevant list gave them a new purpose and saved them.
For Carter, who is the main protagonist of this episode, it is vice versa: as a cop (like Fusco) she is used to working with a partner or in a team and her main purpose is acting according to the law (the rules) and so being a person of morality. To understand her character we have to look back on her first main episode: Getting Carter (s. 1. ep. 9). The flashback there showed us her experience as an interrogator in Iraq. She is trying to play by the rules and being a decent human. But this doesn't work all the time. And here it is for the first time that someone tells her: You are all alone! - meaning the world around you isn't like that, it is bad.
During that episode we also hear Moretti in prison telling her the very same thing: he snears at her and asks for her backup and points out that she is acting alone.
We later hear Elias shouting the same thing to her in the episode Flesh and Blood when he tries to get through the steel door: "You are all alone and no one is coming to save you; Carter answers: "I am not as alone as you think". (then Reese saves Taylor while Fusco saves Carter)
The one person she is always coming back to is John. She has a special relationship to him (and the kiss in the next episode that so many disliked because he came "out of the blue" was a logical development for me).
John has his own special relationship to loneliness. We learned that in his airport flashbacks that were repeated several times because of their importance. "In the end we're all alone, and no one is coming to save you". (Reese couldn't come for Jessica, but he will definitely come for Joss). And so it is John who tells her in their first meeting after she gets shot by her CI: You are not alone!
The motive of being alone vs. asking for help is also reflected in the flashbacks to her former husband Paul, who rejected help after his problems of being a soldier and refusing help.
Cal Beecher's death has proven to her that she can no longer relay on the law, she starts her investigation into HR alone, because she knows how dangerous this is and she wants to protect her friends by it. Lasky's death throws her over the brink of her rules once and for all. Although she has to ask Shaw for "firepower" she doesn't bring her into the project and she rejects John's help because she doesn't want to kill Alonzo but get him arrested properly. John's help because of his shady background could endanger that. But she starts a gang war and that is something very extreme for a cop like Carter. How far she has come shocks Harold and John when they find out.
We see her conflict when she tricks Fusco so that she can finish this alone, but still she trusts him with the backup of her material, which will consequently bring Fusco and his son into grave danger later. And she is not sure about asking for John's help, we see her NOT calling him (nice trick for the suspense).
What turns it around for her is her phonecall to her son Taylor who tells her: "Whatever you're doing you don't have to do it alone. Lots of people care about you. If you ever need any help, all you have to do is ask." (meaning: you are not alone, everyone is relevant to someone).
Even Alonso talks about her fight alone: "You see yourself as the protagonist in a tragedy determined to face the world alone". And then: "My fault I didn't kill you along with Cal so neither of you would have to die alone."
But she did call John offscreen and Finch monitors the endgame and even records Alonzo's confession. All hell breaks loose when John enters and than he and Carter are on the run with their captive and John's picture is out there for all the dirty cops. So Carter was right in her fear for the danger this would mean for her friends because now it is John's turn that his number will come up.
All of our main team members were at one time in their life thrown into a situation of extreme loneliness: Finch after Nathan's death, John after he got betrayed by the CIA and learning about Jessica's death, same fate for Shaw after getting betrayed by Control and Cole's death and Root very early on when no one believed her after the kidnapping of her friend, she later run away from home and was on her own all her life. Nathan's little project of the irrelevant list gave them a new purpose and saved them.
For Carter, who is the main protagonist of this episode, it is vice versa: as a cop (like Fusco) she is used to working with a partner or in a team and her main purpose is acting according to the law (the rules) and so being a person of morality. To understand her character we have to look back on her first main episode: Getting Carter (s. 1. ep. 9). The flashback there showed us her experience as an interrogator in Iraq. She is trying to play by the rules and being a decent human. But this doesn't work all the time. And here it is for the first time that someone tells her: You are all alone! - meaning the world around you isn't like that, it is bad.
During that episode we also hear Moretti in prison telling her the very same thing: he snears at her and asks for her backup and points out that she is acting alone.
We later hear Elias shouting the same thing to her in the episode Flesh and Blood when he tries to get through the steel door: "You are all alone and no one is coming to save you; Carter answers: "I am not as alone as you think". (then Reese saves Taylor while Fusco saves Carter)
The one person she is always coming back to is John. She has a special relationship to him (and the kiss in the next episode that so many disliked because he came "out of the blue" was a logical development for me).
John has his own special relationship to loneliness. We learned that in his airport flashbacks that were repeated several times because of their importance. "In the end we're all alone, and no one is coming to save you". (Reese couldn't come for Jessica, but he will definitely come for Joss). And so it is John who tells her in their first meeting after she gets shot by her CI: You are not alone!
The motive of being alone vs. asking for help is also reflected in the flashbacks to her former husband Paul, who rejected help after his problems of being a soldier and refusing help.
Cal Beecher's death has proven to her that she can no longer relay on the law, she starts her investigation into HR alone, because she knows how dangerous this is and she wants to protect her friends by it. Lasky's death throws her over the brink of her rules once and for all. Although she has to ask Shaw for "firepower" she doesn't bring her into the project and she rejects John's help because she doesn't want to kill Alonzo but get him arrested properly. John's help because of his shady background could endanger that. But she starts a gang war and that is something very extreme for a cop like Carter. How far she has come shocks Harold and John when they find out.
We see her conflict when she tricks Fusco so that she can finish this alone, but still she trusts him with the backup of her material, which will consequently bring Fusco and his son into grave danger later. And she is not sure about asking for John's help, we see her NOT calling him (nice trick for the suspense).
What turns it around for her is her phonecall to her son Taylor who tells her: "Whatever you're doing you don't have to do it alone. Lots of people care about you. If you ever need any help, all you have to do is ask." (meaning: you are not alone, everyone is relevant to someone).
Even Alonso talks about her fight alone: "You see yourself as the protagonist in a tragedy determined to face the world alone". And then: "My fault I didn't kill you along with Cal so neither of you would have to die alone."
But she did call John offscreen and Finch monitors the endgame and even records Alonzo's confession. All hell breaks loose when John enters and than he and Carter are on the run with their captive and John's picture is out there for all the dirty cops. So Carter was right in her fear for the danger this would mean for her friends because now it is John's turn that his number will come up.