Original sentence: Proposals in 1934 for an "eastern Locarno" pact securing Germany's eastern frontiers foundered on German opposition and on Poland's insistence that her eastern borders should be covered by any western guarantee of her borders
Edited sentence: Proposals in 1934 for an "eastern Locarno" pact securing Germany's eastern frontiers foundered on German opposition and on Poland's insistence that her 1920 territorial gains from the Soviets should be covered by any western guarantee of her borders