In the contemporary environment, significant changes occur in comprehending the forms of threats to the security of states. This refers particularly to the so-called military threats, and the term war is ever more often replaced with other terms, such as aggression, armed conflict, and armed uprising and other conflicts where armed force is involved. The above-mentioned forms of military threats to the security are stated in the Defense Strategy of the state union of Serbia and Montenegro. All these terms, explicitly and implicitly, involve armed struggle as the main characteristic of the conflicts. That is why the syntagm of armed struggle takes on new contents that have to be incorporated in its definition and classification.