 Complete the following phrase:  Rudolf Hamburger was taught to sketch by Friederich Iwan, a local artist, while he was still a boy. He successfully completed his schooling and moved to Munich to study architecture in 1922. The assassination of the Foreign Minister, Walter Rathenau, that year came as a particular blow. Rathenau had been a close personal friend of his fathers: the shocking event and the rising tide of right-wing extremism, which was 