This paper sets to offer a definition and a characterization of civil peace construction experiences in Colombia since 1978, with a special interest on the first presidential term of Alvaro Uribe Velez (2002-2006), specifically, regarding his policy of Defense and Democratic Security. In the paper an analytic and descriptive perspective is assumed regarding the incidence that the set of political opportunities has had on these peace experiences. In order to do so, the paper makes use of a framework of analysis of some of the more useful inputs of theories used in the study and characterization of social movements and new social movements; specially those offered by Alberto Melucci.