"The Wall was in the long run a propaganda catastrophe for the East. Every day it existed, it screamed aloud one simple, damning statement: in Berlin we Communists stood in direct competition with capitalism, and we lost. Khrushchev and his successors had to live with this permanent mute accusation until a Soviet leader came along who just couldn’t or wouldn’t do it any more."
January 1, 1970
https://en.wikiquote.org/wiki/Berlin_Wall