第二次世界大战后，国际政治生活中出现了两个特别引人注目的现象：其一是一些分裂的国家重新统一了，如德国、越南和也门等；其二是一些原本统一的国家又分裂了，如苏联、南斯拉夫和捷克斯洛伐克等。分裂国家为什么能重新统一？统一国家又缘何会出现分裂？本书与你一起研究和探讨国家的统一与分裂问题，如德国、越南和也门等的重新统一给仍处于分裂状态的国家提供了哪些宝贵的经验？苏联、南斯拉夫和捷克斯洛伐克等国的分裂又为那些多民族国家如何保持统一防止分裂提供了哪些有益的教训？都将一一进行分析。 ( After World War II, there were two particularly striking phenomenon in the international political life: The first is that some disrupted countries reunited, such as Germany, Vietnam, Yemen etc.; the other is that some originally united countries disrupted again, such as the Soviet Union, Yugoslavia, Czechoslovakia, etc. Why can disrupted countries be reunified? And why can united countries be disrupted? This book will study and discuss on the issues of unification and disruption together with you, for example, which valuable experiences the reunification of Germany, Vietnam and Yemen offers to the countries that are still in a state of disruption? And which useful lessons the disruption of the Soviet Union, Yugoslavia and Czechoslovakia and other countries offers to those multi-ethnic country on how to maintain unified and prevent from disruption? These will be analyzed one by one.)