But it also limited the federal government 's politics , and in the 1960s it became more and more difficult to maintain .
The doctrine seemed to succeed for a long time in isolating the GDR , at least from important Western or Third World states .
GDR also limited the federal government 's politics , and in the 1960s GDR became more and more difficult to maintain .
The doctrine seemed to succeed for a long time in isolating the GDR , at least from important Western or Third World states .