The author focuses on Hans Kohn (1891-1971) who is generally regarded as the founding father of modern Anglophone academic research on nationalism. He was first to adopt a more neutral stance toward nationalism, one that made sustained attempt at dispassionate analysis of the phenomenon in order to define, classify and explain it. However, not only did he bring in a innovative and novel perspective to the subject by producing broad comparative studies but he was responsible for introducing one of the basic and long-lasting themes to the study of nationalism, namely a strongly moralistic distinction between a good nationalism, which he associated with the West, and a bad nationalism allegedly typical for the non-Western world. The paper discusses three questions: first, how did Kohn conceptualize the differences between the two types of nationalism? Second, how and why did he come to his conclusions and, finally, if it can be argued as many authors claim, that his discrimination between the two types of nationalism are valid and useful?