While she feels immense guilt and sorrow for Rue's death, she understands that it was not simply the actions of one person (like Marvel, who killed Rue), but a result of the Capitol's cruel and manipulative games designed to cause suffering and death.
Here's why:
* The Capitol's games: The Capitol deliberately creates a situation where children are forced to fight and kill each other for entertainment. It is this system that ultimately leads to Rue's death.
* Lack of support for tributes: Katniss observes that even the Gamemakers, who are supposed to oversee the Games, do not care about the tributes' well-being. They are simply pawns in a game of entertainment for the Capitol.
* Exploiting the tributes' emotions: The Capitol uses the tributes' emotions and desperation against them, manipulating them for their own entertainment. This is shown by the Capitol's reaction to Rue's death, using it as a spectacle and fueling their own entertainment.
Katniss's anger at the Capitol is a driving force throughout the series, fueled by the loss of Rue and her determination to fight against the system that caused it.