By the end of the twentieth century, there were many secessionist groups, but, the move towards Taiwanese secessionism has arguably been the most significant of these. It triggered the 1996 Taiwan Strait Crisis, which resulted in a historical military confrontation between Mainland China and the US. As will be shown, from 1988 to 2000, Lee Teng-hui, as president of Taiwan, manipulated the political Cross-Straits relationship to promote what was ultimately a secessionist policy. This caused Mainland China to react strongly and triggered sharp tension between Taiwan and Mainland China. This thesis considers what motivated Lee Teng-hui to implement a secessionist Cross-Straits policy and why he supported unification while adopting a substantive secessionist policy. It looks at how he was able to instigate Taiwanese hostility towards Mainlanders, to transform the hostility into a sense of Taiwanese national identity and ultimately into Taiwanese secessionist ideology. A historical approach was used in exploring the origins of secessionism, and descriptive and analytical methods to review systematically and comprehensively political developments in the ROC and its civil war, and to study Lee Teng-hui’s life; the national identity of Taiwan and Mainland China; the implementation of Lee Teng-hui’s political Cross-Straits policy; and the reaction of Mainland China. The study showed that the main cause of Taiwanese secessionism was ethnic conflict between Taiwanese and Mainlanders. It originated from the 228 Incident of 1947, in which Mainlander-led troops slaughtered many Taiwanese. Soon after, the Mainlander-led government fled to Taiwan from Mainland China, and many Taiwanese (including Mainlanders) were killed during the State of Emergency in the 1950s and 1960s. Since the Mainlander-led government fled to Taiwan in its original central government form, the Mainlander élite occupied key positions in the government during the 1950s and 1960s. It resulted in unfair power-sharing for Taiwanese, and caused the Taiwanese élite to believe that they had to establish their own government (nation). Lee Teng-hui had participated in the CCP and had been under political surveillance by the Mainlander-led government for over twenty years. He weathered these political difficulties, but by reasonable inference, there was a close relationship between the political oppression by the Mainlander-led government and his secessionist political Cross-Straits policy. Because Taiwanese residents were indoctrinated by Chiang Ching-kuo and his father, Chiang Kai-shek’s administration for about 40 years, Chinese ideology was dominant and Lee Teng-hui initially paid lip-service to Cross-Strait unification whilst working towards secessionism as reflected in the Chingdao-Lake Incident (1994); the private dialogue between Lee Teng-hui and Shiba Ryotaro (1994); the address at Cornell University (1995); and his two-state theory (1999). However, due to strong pressure from Mainland China, he did not reach his secessionist goal during his presidential term (1988-2000). In conclusion, this thesis shows that Taiwan Island’s geopolitical importance is at the heart of the US’ support for Taiwan’s secession from the Mainland. Therefore, Lee’s secessionist Cross-Strait policy aside, US national interests lie in containing Mainland China and it has, therefore, always played an important role in the secessionist issue and always will. From the perspective of Mainland China, either in terms of nationalism or national security, Taiwan’s secession is a life-and-death issue. If Taiwanese authorities were to declare independence, the only option for Mainland China would be to launch a unification war. For the US, Taiwan is only a pawn that it uses to contain Mainland China. Therefore, in the Cross-Strait issue, the US has more options than Mainland China, namely, to use military intervention in the future to deter Chinese unification or to decide to share common peaceful international relations with Mainland China by accepting Cross-Strait unification. / Thesis (DPhil (International Relations))--University of Pretoria, 2004. / Political Sciences / unrestricted