Why do political leaders often perform fatal miscalculations, take ill-considered actions, and indulge in ludicrous wishful thinking? This book seeks to shed light on these questions by conducting two related case studies from the vantage point of the science of human behavior--psychology. The first one analyzes the decision-making behavior and leadership style of Mao Zedong, a man who, in the words of historian Maurice Meisner, "conceived and led the most popular revolution in world history" only to squander its fruits by embarking on a series of catastrophic political projects that cost tens of millions of Chinese their lives. The second case study follows the path of Mao''s successor, Deng Xiaoping, who renounced his faith in Maoism and embraced a pragmatic decision-making approach that paved the way for China''s remarkable rise.This book is the result of five years of research. Despite being based on the author''s PhD dissertation, this work should be accessible to non-experts. The investigation begins in Chapter 1 with a historical overview of China''s accelerating decline throughout the nineteenth century. This introductory chapter depicts China''s so-called century of humiliation (1839-1949). It offers some context as to the repeated failures to achieve national rejuvenation over the decades. The psychological analysis starts in Chapter 2 with a detailed discussion of Mao''s restlessness. The author will argue that Mao was locked in a never-ending battle against recurring self-doubts, which left him with a constant need for reassurance--a need that he attempted to satisfy by seeking to overcome ever more formidable political challenges. This, in turn, condemned China to a state of uninterrupted mass political campaigns, which greatly interfered with the nation''s attempts at economic and social modernization. Chapter 3 analyzes why Mao''s colleagues went along with his utopian visions. The discussion here will demonstrate that the decision-making behavior of the Chinese leadership exhibited all the hallmarks of groupthink--a modus operandi whereby the yearning to retain the approval of one''s leader as well as one''s colleagues outweighs the desire to draft effective policies. Chapter 4 explores how and why Mao''s principal goal in life eventually shifted from building socialism in China to preventing an imaginary capitalist restoration--a shift that ultimately paved the way for the disastrous Cultural Revolution. The author interprets this shift in Mao''s narrative identity as a reaction to his repeated failure to advance the quest for modernization. Chapter 5 centers on Deng''s silent rebellion against Mao''s decision-making approach. The discussion here will showcase the power of self-reflection--a psychological exercise that subjects one''s past behavioral and thought patterns to ruthless scrutiny so as to learn lessons for the future. Having subsequently renounced his faith in Maoism and all other "isms," Deng espoused fact-based and practice-oriented decision making. Yet, this did not turn either him or the decision-making apparatus over which he presided into dispassionate robots. Beliefs and values, as shown in Chapter 6, still colored how Deng and his colleagues interpreted complex developments in China. These beliefs and values were shaped by the forces of personality, the power of worldviews, and the subjective manner by which different decision makers processed their past experiences. As a result, the senior leaders greatly differed in terms of their visions for advancing China''s quest for modernization. Chapter 7 concludes this book with a summary of the most important findings. It also elaborates on the question of how the developed hypotheses can be validated. Further, this chapter provides an overview of the most pronounced behavioral characteristics of both Mao and Deng.