Class
The division between the classes in Panem is pronounced. The poorest of the Districts have no opportunity to change their circumstances. There is no chance for social mobility as citizens are forbidden from leaving their Districts. If a person is born in 12, he or she will either be a coal miner or have a miner in the family. District 12 citizens are all forced to make ends meet through brutal winters, living on scraps and what they can trade for in the black market. At best, they can expect to scrape by.
The Capitol, modeled after the mythic excesses of Ancient Rome, is a place of gilded indulgence. Lavish feasts and strange beautification practices are commonplace. Every whim is met and all things are possible. Katniss is horrified to learn of a drink that makes people throw up when they are full so they can continue to gorge themselves at parties. If life in the Districts is defined by not having enough, life in the Capitol is its extreme opposite. Worse, everything the Capitol enjoys is provided by people in the Districts. The rich are literally living off the backs of the poor.
The rebellion begins to take shape in Catching Fire as the government begins to push people in the Districts beyond their breaking point. Class disparity is at the heart of the revolution.
Rebellion/Revolution
Katniss's political awakening blossoms in Catching Fire. Though she is already a reluctant symbol for the revolution, she only slowly realizes that she must play a part in it. As she matures and continues to gain self-awareness, Katniss realizes the necessity for an uprising. This discovery unfolds during the Victory Tour and reaches a turning point after Gale is beaten.
During the Victory Tour, Katniss gets her first glimpse of life in other Districts. She has been warned to stick to a script that sells her relationship with Peeta and dispels the defiance behind her act in the Hunger Games. This plan falls apart during the first stop in 11. Katniss is unable to keep silent and she gives her heartfelt thanks to the families of Rue and Thresh. Her speech is met with an orchestrated salute which culminates in the death of an elderly man and two others. Katniss sees that the tide of rebellion is not going to be turned by a few kisses with Peeta. The revolution is about something bigger than her.
Rue reminded Katniss strongly of her sister Prim, the person she has sacrificed the most for. When Katniss returns from the Victory Tour, she decides she must run away with her sister and other loved ones to escape the grasp of President Snow. Gale, however, is horrified by this plan. The uprisings are reaching fever pitch and the time he wants to support the rebels when they declare all-out war. At first, Katniss doesn't understand why Gale would choose such a dangerous path. After he his beaten, she realizes that they are already in danger, and have been their whole lives. She realizes that Prim suffered abuse her whole life at the hands of the government. For Katniss, it is when the political becomes personal that she takes up the mantle of revolutionary, determined to keep her loved ones safe.
Love and Loyalty
While there is a love triangle in Catching Fire, romantic love takes a backseat to loyalty. Katniss has strong feelings for both Gale and Peeta though she is unable to commit fully to either one. Romance is a luxury Katniss cannot afford. With the President on her tail in District 12 and all manner of enemies bearing down on her in the arena, she has no time to ponder romantic love. But above all things, Katniss she prioritizes familial love and loyalty to those she trusts. After the death of her father, Katniss was forced into the role of parent and provider, which honed her survival skills but also set a precedent for self-sacrifice. Volunteering for Prim in The Hunger Games was, at the time, simply the latest occurrence of her placing her sister's needs above her own.
Katniss continues her selfless behavior in the arena, taking an entirely objective stance on the Games, even if it means her own death. In the Quarter Quell she decides to keep Peeta alive by any means necessary in order to repay her debt to him and also ensure his future, including children, because it is what she feels he deserves. Even though the objective of the Games is to kill or be killed, the tributes make deep connections with one another. Katniss gathers new family - Mags, Finnick, Beetee and Wiress and, reluctantly, Johanna. Even though she weighs the strategic benefit of double-crossing her allies, their debts accrue and Katniss knows how difficult it will be to kill someone who has shown her loyalty.
In the arena, however, love can be a liability. Jabberjays are programmed with the voices of those closest to the tributes in order to cut them to the bone. Prim's tortured voice does more damage to Katniss than a poisonous fog could ever do. Even Finnick, normally so cool and flirtatious, has a love that can be used against him. Only Johanna is not afraid of the jabberjays. Johanna admits later that this is because she has no one to love which, to Katniss, is a fate worse than death.
Coming-of-Age
Katniss's journey throughout the first two books can be viewed as an extreme version of a coming-of-age tale. At 16, Katniss has lived through the death of her father, her mother's psychological break, and extreme poverty. By 17, she has killed or witnessed the deaths of dozens of other teenagers in a gladiator-like tournament and become the linchpin for a revolution. Though she is significantly more hardened and wizened than an everyday teenager, Katniss still faces the same uncertainty throughout Catching Fire.
Through her first-person narration, readers can get a sense of Katniss's indecision and impulsiveness. She either belabors every decision or makes quick moves without fully weighing the consequences of her actions. She can be calculated, practical and stoic. She can also be easily angered, confused or self-critical. Like most teenagers, Katniss is trying to figure out her place in the world. Granted, her world is much different than that of her readers, but she still must figure out a way to balance her family with the expectations of authority figures. Katniss is also thrown for a loop by the romantic overtures of Gale and Peeta. She feels strong emotions for both of them in different ways and times, but can't quite get a grasp on that aspect of her life. All of these problems, when stripped of context, are elements of coming-of-age tales. Katniss is first and foremost a teenager, which is part of the reason that readers and viewers find her character so relatable.
Sacrifice
There are several incidents of sacrifice in Catching Fire. After all, it is the second book in a trilogy that begins with a key moment of sacrifice: Katniss volunteers to take her sister Prim's place in the reaping for the Hunger Games, setting forth the action of the rest of the series. Katniss is a protector, always willing to go without or do what is necessary in order to save her loved ones. Volunteering for Prim was simply an extension of what Katniss had done her whole life - put her family first.
For her second Games, she decides the only outcome she could live with would be to try to ensure Peeta outlasts the other tributes, including herself. Katniss believes he has a better chance of living a full life and, furthermore, she owes him. In the arena, as in daily life, Katniss is drawn to people with similar values and does not necessarily feel the need to go with the tide. She allies with Mags because she admires the way elderly Mags volunteered for Annie Cresta in the Quell. Katniss's instincts about Mags prove to be right when Mags sacrifices herself in the fog to save Katniss, Peeta and Finnick in the arena. Working for the rebels, Mags lays down her life for the greater good.
Oppression
President Snow and his government maintain an iron grip over the Districts of Panem. Though some Districts, like 1 or 2, are better off than others, the amenities in the District are kept at subsistence level. Katniss's District 12, the poorest District, has been gripped with poverty for as long as either Katniss or her mother can remember. They have lived their lives doing what is necessary to survive, including working in dangerous jobs assigned to them by the government. Snow's government believes that keeping its citizens hungry diminishes their hope and ensures they will keep performing in order to feed their families. However, as becomes apparent in Catching Fire, there is a limit to how much the Districts will take.
In this novel, Snow steps up authority measures considerably in order to quell uprisings in the Districts. He assigns brutish Peacekeepers to violently uphold laws that have not been enforced for years. The new regime makes sure to burn down the Hob, 12's black market, even though prior officials were known to not only tolerate it, but patronize it as well. Stockades and whipping posts soon appear in the square. These measures are complimented by shut downs in the mines or factories in the Districts. Without work, the Districts' citizens are pushed to the brink of starvation.
Misinformation is another key tactic used by the government. When Katniss visits District 11, she learns that the population is much larger than what she has seen on TV. By limiting who knows what about the rest of the country, the government can remain in power. Even though life in the Capitol is filled with indulgence and excess, the citizens who live there are still being oppressed, albeit in a less tangible way. They are largely unaware of life in the Districts, just as those in the Districts have no idea what the Capitol is like. When the uprisings begin, the citizens in the Capitol are told that the goods from the revolting Districts are delayed due to "bad weather", rendering them completely unaware of the human suffering that surrounds them.
The Power of Media
One of the tactics that President Snow's government employs to keep the Districts in line is manipulating the media. Collins was influenced by the proliferation of Reality TV and its juxtaposition with footage of the Iraq war. In her novels, the spectacle of the Hunger Games and its accompanying interviews, parades and tours are designed to distract the citizens of Panem from the reality of life in their country. People born in the Capitol know little of life in the Districts and vice versa. The only exposure they have to life outside of their homes comes through television, and these narratives are heavily controlled by the government. News reports and images of real events are doctored or transmitted only to District mayors. An entire District is believed to have been destroyed in the war but the truth of its existence is unpacked by astute viewers of broadcasts from 13. Even Katniss and Peeta are no strangers to the media. They have to present star-crossed versions of themselves to the adoring crowds in order to, at first, win favor from the crowd and, later, to survive. In Panem, they soon learn, nothing on television is to be trusted.