[A] particular socialist state, staying in a system of other states composing the socialist community, cannot be free from the common interests of that community. The sovereignty of each socialist country cannot be opposed to the interests of that community. The sovereignty of each socialist country cannot be opposed to the interests of the world of socialism, of the world revolutionary movement. . . . Discharging their inter-nationalist duty toward the fraternal peoples of Czechoslovakia and defending their own socialist gains, the USSR and other socialist states had to act decisively . . . against the anti-socialist forces in Czechoslovakia.
Id. at 1170.