Big difference. They shot those trying to leave, not enter. And yes, it was of equally paramount importance for them as for the U.S. to control who can enter:

Big difference. They shot those trying to leave, not enter. And yes, it was of equally paramount importance for them as for the U.S. to control who can enter: this is how Communism works. If you let people leave, they vote Communism out of existence, with their feet.