The rise of radical Islamism in recent years does not limit the applicability of the concept of cultural nationalism. Rather the two are intertwined in ways which this article will attempt to highlight. Islam took specific national forms as modern nation-states arose and the contemporary resurgence of radical Islamism also follows that modern pattern. I examine the emergence of the three most important movements in the Islamic world, namely, the Muslim Brotherhood in Egypt, Jama'at-e Islami in Pakistan and Khomeinism in Iran. I argue that imperialism, authoritarianism and the contemporary rise of radical Islamism are closely related. More particularly, the latter is the complex product of failed modernisation programmes, failed developmentalism under the auspices of international capital and in collaboration with the local propertied classes, and corrupt, undemocratic governments throughout the Islamic world. The failure of secular left and liberal nationalist movements to attract mass-based support has also contributed to the strengthening of radical Islamists. The article concludes that the mobilising power and populist appeal of radical Islamists can be challenged effectively only if the social, economic and political factors that give rise to these movements in the first place are eliminated.