Mr Mueller warned such divides cause "slavery and pain" and would "destroy the lives of millions".

The German city was divided by the Berlin Wall from 1961 to 1989.
I believe the primary objective of the Berlin Wall was to keep people from leaving, not entering. Nobody wanted to enter communist controlled East Berlin in those days, but most folks certainly wanted to leave for the Us/French/British controlled sections in West Berlin. Our wall, on the other hand, is being constructed to keep illegals, potential terrorist, and drugs out.