[1] He is known for his theorization of mediology, a critical theory of the long-term transmission of cultural meaning in human society, and for associating with Marxist revolutionary Che Guevara in Bolivia in 1967 and advancing Salvador Allende's presidency in Chile in the early 1970s.

In this capacity, he developed a policy that sought to increase France's freedom of action in the world, decrease dependence on the United States, and promote closeness with the former colonies.

This was in defence of French laïcité (separation of church and state) which intends to maintain citizens' equality by the prohibition of religious proselytism in the school system.

His recent work investigates the religious paradigm as a social nexus able to assist collective orientation on a wide, centuries-long scale.

Debray is the initiator and chief exponent of the discipline of médiologie or "mediology", which attempts to scientifically study the transmission of cultural meaning in society, whether through language or images.

In a February 2007 opinion-editorial in the newspaper Le Monde, Debray criticized the tendency of the entire French political class towards conservatism.

He also deplored the influence of the "videosphere" on modern politics, which he claimed has a tendency to individualize everything, forgetting both past and future (although he praised the loss of 1960s "messianism"), and rejecting any common national project.

He criticized the new generation in politics as competent but without character, and lacking ideas: "So they [think they] have recruited philosophy with André Glucksmann or Bernard-Henri Lévy and literature with Christine Angot or Jean d'Ormesson".