The fate of Musa bin Nusair and Muhammed bin Qasim is a lesson of historical importance. With the ascension of Muawiya, legitimacy of rule was no longer by consent of the masses; it was by force. Sultan after sultan arose and established himself by dictate or by virtue of inheritance from soldier-conquerors. When a ruler was competent and just, as happened with Omar bin Abdul Aziz, the common people enjoyed some freedoms. When he was a tyrant, as happened with Sulaiman bin Abdul Malik, the people suffered. Since the period of the first fourCaliphs, Muslims have not shown an institutional capability to evolve and nourish their political leadership from among the masses. When the body politic throws up its first echelon of leadership, the tendency has been to destroy that leadership, unless the leader survives through shrewd maneuvering or ruthless imposition. This inability to cultivate and nourish political leadership from the bottom up has defined the limits of Muslim power and in a broader sense, the achievements of Islamic civilization. The survival of potential leaders has always depended on the whims of the despot at the top or of his local political cronies.

A second lesson from the tragic deaths of these two outstanding generals is that the internal dialectic of the world of Islam has defined the limits of its reach. Having completed the conquest of Spain, Musa bin Zubair was ready to launch an invasion of France when he was called back. He might well have succeeded in this goal because there was as yet no strong leader into resist a determined assault. By the time the Muslims did come around to venture into central France, Gaul had a strong leader in Charles Martel and the Muslims were forced to turn around at the Battle of Tours (737). Similarly, Muhammed bin Qasim had successfully penetrated the Indian defenses in the IndusRiver basin. Given a green signal from Damascus and Kufa, he might well have extended the dominions of the Caliphate into the Gangetic plains. This was not to be. Mohammed bin Qasim was called back from Multan just as he prepared to launch a major thrust beyond the Indus River. Northern India remained in Rajput hands for the time being. It was not until the victory of Mohammed Ghori at the Battle of Panipat (1191) that the Muslims captured Delhi. In both cases, it was the internal turmoil in the Muslim body politic that was the determining factor in the arrest of the Muslim advance.

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