Forty years ago, on August 21, 1968 the armed force of the Warsaw Pact entered Czechoslovakian territory and put an end to the economic and political liberalization reforms initiated by a moderate Communist leader Alexander Dubcek. Supposedly, it was feared by the Soviet leaders that a liberalized political movement within Czechoslovakia might ultimately lead to a weakening of the Soviet bloc and the Warsaw Pact alike. Also, the Soviet leaders must have been afraid of the so-called spill-over effect that would initiate similar political activities in the remaining states of the Soviet bloc. It was claimed by the Communist propaganda that the invasion was a lawful exercise of the collective self-defense against anti-communist activities. It has been argued by the Soviets that it was not only a right, but the duty of socialist states to intervene if the socialist achievements were endangered by the “imperialist” activities.
The invasion is thus a typical example of the so-called Brezhnev Doctrine of limited sovereignty (“Doctrine”). The Doctrine aimed at limiting the prohibition of the use of force stipulated by Article 2(4) of the UN Charter. It explicitly allowed for forcible reaction should the internal situation endanger the vital interests of socialism. It also claimed that the internal situation in such a state is not only a problem of the country concerned, but a common concern of all socialist countries. Undoubtedly, such a doctrine was a clear violation of the UN Charter, namely of Article 2(4). The Doctrine must be strictly refused as it does not represent an exception provided for in the UN Charter. The Doctrine does not even find any support in customary international law.
The proposed justification of the invasion has not found support within the international community, which was not receptive of the broadening of the right of self-defense. The disapproval is demonstrated by deliberations in the Security Council on August 21, 1968, where it was declared by the majority of its members that the armed forces of the Warsaw Pact committed an act of aggression. It was further described as an illegal intervention in Czechoslovakian internal affairs. Regrettably, there was no condemnatory resolution adopted. Apart from raising the issue in the United Nations, the international community did not take any other action. The Brezhnev Doctrine was finally abandoned in the late 1980s when Mikhail Gorbachev declined to use military force against Eastern European countries.