A nonviolent form of defense against invasion or internal overthrow of a regime. This technique was well documented and made somewhat known to the public by Gene Sharp in works such as The Politics of Nonviolent Action (3 vols., 1973) and Civilian-Based Defense: a Post-Military Weapons System (1990). In CBD the citizens organize to resist the invasion or overthrow by nonviolent, or at least non-violent means such as strikes, defiance of military orders, fraternization, etc. CBD works well when the citizens can separate the attackers as people from their actions, accepting and seeking to win over the former while resisting the latter — if necessary, to the death. The best known modern example of CBD is Prague Spring, when over eight months, from January to August of 1968, Czech citizens resisted a Warsaw-Pact invasion aimed at suppressing the liberalizations of the popular president Alexandr Dubček — a military action that the Kremlin anticipated would take only four days. The methods used were fraternization, humor, and mild forms of sabotage such as painting over or turning road signs to mislead troop movements. In the end the uprising was overcome, but at a great propaganda cost to the Eastern Bloc — and no doubt an inspiring lesson to the Czechs, who would go on to use nonviolent means to separate from the weakened Communist power some twenty years later. Along with Third Party Nonviolent Intervention, CBD is now regarded by some as a nonviolent answer to war.