There are numerous studies of the process that led to Truman's decision to intervene in Korea. But there has been little authoritative information about the perceptions and policies of Stalin, Mao and Kim Il Sung, the communist leaders who initiated the conflict. This volume, the result of collaboration between Russian, Chinese and American scholars, seeks to fill the gap.
Although a prodigious amount of research went into this volume, it is not, and cannot be, definitive. As the authors themselves point out, "there is a continuing paucity of Soviet materials." Indeed, on many crucial questions, the authors are reduced to merely citing Russian archivists who have had access to the archives. Moreover, the presidential archives in which Stalin's papers are held remain closed, which they do not make clear. What they say is that prior to April 1950, two months before the attack, Stalin was cautioning Kim Il Sung about the danger of a wider war. Stalin was prudent, and he feared getting involved in a wider war with the United States. But after April 1950, according to a Soviet diplomat who had access to the archives, Stalin "for some reason changed his mind and began to push for a military solution very actively." What is not clear from this volume is why Stalin changed his mind.
On this critical point, the authors are reduced to speculation. They pile explanation on explanation, most based on conjecture about Stalin's motivations. This is not to detract from their achievement. This volume assembles a great deal of information and will be essential reading for historians who follow the subject. The final word on Stalin's motivations for changing his mind in April 1950, if indeed that was the case, will have to await the opening of the Stalin archives.
One final point: students of deterrence theory will find nothing here to contradict their long-held view that the U.S. failure to include Korea in the U.S. defense perimeter helped convince the prudent Stalin that he could achieve a major victory without great risk. Stalin was constantly scrutinizing U.S. policy for signs of resolve or a lack thereof. Thus, if the United States had taken a stronger line on the importance of defending Korea in early 1950, the Korean War might have been averted.