In talking about motivations of Islamists, it is probably most accurate to say that there is no one motivation for all Islamists and motivations in the real world can be expected to be mixed and varied. It is easy to talk about geopolitical trends and suggest that Islamism is impacted by postcolonial trends: it is often reacting to the legacies of colonialism. In the extreme example of the minority of violent terrorists, we are most often talking about radicalized individuals with a twisted psychology and motivations. This psychology of radicalized terrorists and suicide bombers is different from the majority of Islamists. There are numerous references that can be made but, for an analysis of suicide bombers, see "Psycho-Political Aspects of Suicide Warriors and Terrorism and Martyrdom: A Critical View from 'Both Sides' with Respect to Cause and Cure." The good news is that such people are only a minority.
In contrast to the dark motivations of terrorists, I will say that there most probably is a much overlooked and most important common aspect for the vast majority of Islamists as well as for the other adherents of all the Abrahamic religions. This is their deeper motivation of love. Love of God, of His Word, of His Prophet's example and the sacred generally motivates the Islamists. Muslims see the Qur'an and the legacy of the Prophet Muhammad rather analogously to the way that many Christians and Jews contemplate the Ten Commandments. It is not difficult to find an opinion that the Ten Commandments are sacred as a covenant and law given by God and each and every one of them protects our humanity. I would argue that whether or not individual Muslims realize that loving God and His Prophet and following the Qur'an and Sunnah protects our humanity depends on their level of knowledge and awareness. When asked directly, the majority will admit that they should.
My academic research in Pakistan brought me into contact with different contemporary nonviolent Islamists, conservative and liberal and those in between. I met published Islamic scholars as well as senators, politicians, think-tank experts and academics. Upon interviewing them and examining their writings, it is accurate to say that they all appeared to have this deeper common aspect of love as a motivation, even if they rarely discussed it in depth.
It should be noted that the mega-trend of expanded involvement of religion in politics is happening all over the world and is not only seen amongst Muslims. Scholars who study Judaism and the contemporary Jewish community know that there is tremendous love within Judaism. It is love that motivates the construction of a synagogue and sustains its activities. Scholars who study Christianity and the contemporary Christian world know that there is tremendous emphasis on love within Christianity. It is also love that motivates the construction of a church and that sustains its activities. My studies of Islam and Islamism have brought me to realize that classical and contemporary Islam also have tremendous love within. As with Judaism and Christianity, it is this love that motivates the construction of a mosque and that sustains its activities. In their statements and writings, it can be seen that it is love that motivates this greater majority of the Islamists; love for God, love for the Sacred, His Word and His Prophet, and also love for humanity.
Complicating matters is that the Islamists generally can be described to have taken the perspective not only that respect for the sacred protects our humanity but also that this respect should be taken into politics. Appreciating how centrally important respect for the sacred is in Islam generally explains some of the motivation of contemporary Islamists. At the individual level, it is probably more love and less ideology that is a major motivation. This is the level at which any meaningful communication with these people also must take place. Interreligious dialogue with Islamists, if it is going to be successful, must engage the Islamists in an intellectually and spiritually savvy way, discussing love's work. This discussion of love's work must include the topics that relate to our common concern for the protection of humanity. It is only fair for me to warn the reader that this will seldom be as easy as it sounds.
Of course plenty of people within the Muslim fold and without it see Islamism as a failure and a number of issues are certain to arise in discussion about religion and politics. Muslim calls for establishing Islamic governments and even reestablishing a caliphate should be encountered seriously with any and all necessary critiques thereof. I would argue that the call for a one-man caliphate is simply not practicable in the modern world. In contrast, it can be noted that Mawdudi's notable ideological successor, Dr. Khurshid Ahmad, advocates a consultative Islamic caliphate of many Muslims. Muhammad Iqbal, the poet par excellence of Pakistan, advocated consultation in representative assembly. Again, the question of how Muslims relate to pluralism/other religions is critical here and how Muslims relate to religious pluralism will need to be raised in this discussion. A demand for humane encounter with pluralism needs to be made with everyone in the encounter, of Muslims and of non-Muslims.
It is a perennial reality that we need more reconciliation and mutual acceptance all around. Discussing this common motivation of love could also bring motivation in this direction of mutual acceptance. Although it may all sound rather naïve, it is nonetheless fundamentally true for the vast majority: this deeper motivation of love is the major common motivation amongst all motivations. Love is therefore a common ground and hope for meaningful discussion if we can properly locate it in the interfaith discussion.