Why Did Tiananmen Fail

Why did Tiananmen square fail while the 1989 revolutions succeeded? It seems that both had mass, national support in a struggle against well-armed, ideological regimes that were facing economic challenges. So why did China survive? It seems that because the older generation still believed and held power, the political will to use violence was present. But can that really be the explanation? Cunningham’s account seems to demonstrate repeatedly Tiananmen’s inability to achieve real political change. It almost seems like the regime could function perfectly well while ignoring the protestors. And the more time passed, the greater the challenge to maintain high turnout became. So why couldn’t the 1989 regimes have done the same thing in Czechoslovakia,