Even though some words have been removed, it is still about the Berlin Wall!
Just think about those verses:
"The hooks to my brain are well in" (l. 4)
Children's education was shaped to stir up hate against so-called 'imperialists', 'militarists' and 'human traffickers' which were 'reigning' in Bonn (Capital of West Germany) and Washington.
This is no joke! Remember when people all over the world demonstrated against the hydrogen bomb? There are statements from former pupils from East Germany who said their teacher only allowed them to protest too, if it was against the existence of the AMERICAN hydrogen bomb, as only stupid or evil people would protest against the SOVIET hydrogen bomb!
Of course, they didn't absorb this mentality, but it still had a great impact for the rest of their life.
Even though some words have been removed, it is still about the Berlin Wall! Just think about those verses: "The hooks to my brain are well in" (l. 4)
"I face the impregnable wall" (l. 8)