How does the author use foreshadowing in The Tin Drum?

In Chapter Eight, by climbing the Stockturm and shattering the glass of the Stadt Theater for no particular reason, Oskar demonstrates that power corrupts. Grass suggests that using power destructively, simply because there is no one to stop us, is an essential facet of human nature. This foreshadows the coming of World War II, which Markus warns Mama about. Markus's warnings also illuminate a pragmatic explanation for the war - that many people supported the German cause simply because they realized the Germans were far more powerful than the Poles.