An Ethical Musings' reader inquired: Who are we supposed to support, Sunni or Shiite Muslims?
I'm unclear about the antecedent of the pronoun "we" in the foregoing question. The "we" may be Christians or it may be the United States. Regardless, my answer is quite simply; Support both Sunni and Shiite Muslims.
First, both Sunnis and Shiites are God's children. The issues that divide Islam's two largest communities are irrelevant to non-Muslims. Controversial issues include whether leadership of the Muslim faith community requires a blood tie to the prophet Mohammed (Sunnis say no, Shiites answer yes), whether Muslims have saints and shrines (Sunnis say no, Shiites say yes), and so forth.
Second, Islam in both its Shiite and Sunni traditions is a religion of peace. Islamic extremism has arisen among both Shiites (e.g., Hezbollah) and Sunnis (e.g., al Qaeda). These extremists groups attempt to mobilize Muslims against what they perceive as egregious injustice. Clothing the protest in religious language and ideology adds an emotive power to the protest while concurrently placing the opposition between a proverbial rock and hard place. On the one hand, failing to oppose the protesters actively tacitly cedes their complaints credence and jeopardizes the status quo. On the other hand, actively opposing the protest can easily create the impression that the current regime is non-Islamic and opposed to Allah's call for justice. People and states everywhere should expose injustice for the evil that it is and support progress toward justice and peace. This entails supporting Sunni and Shiite while rejecting extremist groups that adopt a twisted form of either.
Third, Shiite Iran is challenging Sunni Saudi Arabia for hegemony in the Middle East. Since the Shah of Iran's downfall, this centuries old challenge has become a principal source of conflict in the Middle East. The United States, branded by Iran as the Great Satan, has sided with Saudi Arabia, primarily because of oil interests and Saudi willingness to support U.S. foreign policy goals. Saudi trust in the U.S. is eroding. The U.S. government is increasingly open about the potential weakness of Saudi power and Saudi responsibility for having sewn many of the seeds that grew into Sunni extremism. Iran appears to want to reenter the global community. Perhaps this is the moment for U.S. policy to pivot, balancing support for Shiite Iran and Sunni Saudi Arabia. (N.B.: In both Iran and Saudi Arabia, Islam is the officially established religion. However, neither nation's government perfectly embodies Islamic teachings. Indeed, describing either as Islamic is demographic rather than theological; both nation's aim to promote the well-being of their governing elites rather than the fullness of Islamic justice. Of course, a similar assessment holds for allegedly Christian nations, e.g., the now defunct Holy Roman Empire.)