During the course of its long history, the Chinese state gradually expanded into the vast and sparsely populated lands that surrounded it, a process that followed the rhythm of the rise and fall of dynasties in its movements of conquest and retrenchment. Characteristically, this involved the Chinese state in the need for military and diplomatic policies, the classic version of the former being pacification and of the latter the exploitation of differences among the peoples of the border territories, using the barbarians to oppose the barbarians, in order to prevent the coalescence of forces that would threaten the Chinese state. Chiang Kai-shek’s own seemingly intransigent views on the question of self-determination were modified only once after his assumption of leadership during the Republican era.