Mallat's excellent, pathbreaking study reveals the story of the most important intellectual development of our era in Shi'i Islam, what he calls the Islamic Renewal (or, more grandly, the Islamic Renaissance) which took place in the city of Najaf in southern Iraq during the 1960s and 1970s. The renewal focused on two areas of Islam's sacred law, constitutional law, and economic issues (labor law, banking, etc.). How, the jurisprudents asked, from an Islamic viewpoint does one form state institutions and produce and distribute wealth?
Muhammad Baqir as-Sadr (1935-80) provided key answers to these questions in his dozens of books. Two of those answers stand out. According to Mallat, Sadr's brief analysis, Sources of Power in the Islamic State, provided "the blueprint of Iranian fundamental law" after the Islamic Revolution. In a massive and now-renowned study, Our Economics, Sadr almost single-handedly developed the notion of Islamic economics.
All of this had direct political consequences, for ideas developed in Najaf spread through what Mallat calls a "Shi'i International." Ruhollah Khomeini was there in Najaf (though, Mallat adds he was only "one scholar among many") as were Muhammad Husayn Fadlallah and Muhammad Mahdi Shams ad-Din (today, leaders of Lebanon's Shi'is) and Muhammad Baqir al-Hakim (head of the Iraqi Shi'i opposition movement).
In brief, the violent and aggressive politics coming out of Tehran has deeper intellectual roots - and so probably greater staying power - than many of us would like to see.