What is the fine-grained topic of the following text: Cunningham uses Rand's biography to illuminate the policies that led to the economic crash in the U.S. and in Europe, and how her philosophy continues to affect today's politics and policies, starting with her most noted disciple, economist Alan Greenspan (former chairman of the Federal Reserve). Only return the topic.
The influence of Ayn Rand's philosophy on U.S. and European economic policies and politics, with a focus on her disciple Alan Greenspan.