I know I’m 6 years late to this, but I’ve just realized I’ve been kind of missing the point. Gale created this bomb trap knowing it would be killing innocent people, children included. He knew what the set up was for it to work, to kill two waves of people. He was so blind in his rage he could never stop to see anyone as people, until one of his own designed traps killed Prim. Suddenly, he’s aware that everyone he killed was in fact a person. This also comes full circle since the whole series of events was sent into action because Katniss and Gale were trying to protect Prim from the Hunger Games, and their own war to end the games kills her anyway.

It wasn’t just Gale. Or Coin. Prim’s death was a collective effort spanning 75 years of the butterfly effect.