Peace is a requirement for human and environmental protection, a binding yearning for sustainable development that is strongly threatened by wars and eco-social injustices. Among these threats, climate change affects the new generations most predominantly and the most vulnerable people, increasing the risk of conflicts and long-term inequalities. As such, the challenge of young people has been dubbed by them as a "climate war". With the use of a militant and military term for what they consider the battle of their generation, alongside incontestable scientific evidences, they aim to provoke political institutions to accelerate the ecological transition. The article highlights how behind this Youth crusade and to fight against the catastrophic outlook foresaw by experts, there is the need to give life to training ecosystems oriented to the value dimension of fraternity. The contribution appeals to the University, among other training agencies, to form fraternal generations in every area of life and work. No ecological transition will be possible without developing a sensitivity that integrates attention to the environmental sustainability with both civic and solidary concerns. The consequence to omit such concerns would lead to individualistic and functional paradigms in the green field.