https://history.state.gov/milestones/1961-1968/soviet-invasion-czechoslavkia
On August 20, 1968, the Soviet Union led Warsaw Pact troops in an invasion of Czechoslovakia to crack down on reformist trends in Prague. Although the Soviet Union’s action successfully halted the pace of reform in Czechoslovakia, it had unintended consequences for the unity of the communist bloc. ... The Warsaw Pact invasion of August 20–21 caught Czechoslovakia and much of the Western world by surprise. In anticipation of the invasion, the Soviet Union had moved troops from the Soviet Union, along with limited numbers of troops from Hungary, Poland, East Germany and Bulgaria into place by announcing Warsaw Pact military exercises. When these forces did invade, they swiftly took control of Prague, other major cities, and communication and transportation links. Given the escalating U.S. involvement in the conflict in Vietnam as well as past U.S. pronouncements on non-intervention in the East Bloc, the Soviets guessed correctly that the United States would condemn the invasion but refrain from intervening. Although the Soviet crackdown on Czechoslovakia was swift and successful, small-scale resistance continued throughout early 1969 while the Soviets struggled to install a stable government. Finally, in April of 1969, the Soviets forced Dubcek from power in favor of a more conservative administrator. In the years that followed, the new leadership reestablished government censorship and controls preventing freedom of movement, but it also improved economic conditions, eliminating one of the sources for revolutionary fervor. Czechoslovakia once again became a cooperative member of the Warsaw Pact.
And what did we do?
Filming of the 1968 move “The Bridge at Remagen” was interrupted by the Soviet invasion of Czechoslovakia in August 1968. Cast and crew were taken to safety in a convoy of 28 taxis, except for Robert Logan, who stayed behind with film gear in order to capture the invasion on film and photo.
https://www.imdb.com/title/tt0064110/trivia/?ref_=tt_ov_ql_3
Russians have had to pull out of storage those same tanks, the T62 for use in attacking Ukraine.
Three days. Czechoslovakia was free for three days thanks to the rebellion . That was enough for the parents of Sebastian Gorka to escape to the West.
It also temporarily froze the Communist movement in the US. They were heavily involved in the “Peace” movement and but had to support the Soviet invasion which made them look like the KGB-paid puppets that they were.
Invading neighbors is a bad Russian habit.