When the Caliphate finally fell to Ali, disaster soon followed. Mu'awiya, the governor of Syria, outwitted Ali in a famous battle at Siffin (657) by having his men hoist copies of the Quran on their spears causing Ali's forces to stop in their tracks. Ali agreed to mediation and the man who would become known as the first of the Shiite imams was assassinated shortly after by disenchanted former associates.

Mu'awiya moved the Caliphate to Damascus where he founded the Umayyad dynasty (661-750). He was succeeded by his son Yazid, who cut down Ali's second son Hussein at Kerbala in 680, a seminal event in Shia history, and commemorated each year with self-lacerating enthusiasm during the Ashura festival. Thus, the Shiites, celebrating their suffering, sacrifice and martyrdom, became the perpetual also-rans of Islamic history.

The Sunnis are the region's top dog, constituting between 85 to 90% of the Muslim population around the world. (The Shiites are the largest of the faith's many minority sects.) In response to Sunni domination, often founded on force and coercion, Shia scholars and jurists developed defense mechanisms, like the doctrine of taqqiya, or dissimulation, which allows the faithful to dissemble and disguise their real identity and belief for fear of being trounced by a stronger power - i.e., the Sunnis.

Open warfare between the two sides has been sporadic, hardly surprising given that the Shia are greatly outnumbered. But mutual hostility is never-ending. Many Sunni Arabs, like Egyptian President Hosni Mubarak, believe that Shiites are more loyal to Iran than to the countries they are living in. There's also an entire sectarian folklore, some of it grotesque. For instance, in Lebanon I have encountered Sunnis who actually believe that Shiites have little tails. Much of the anti-Shia calumny tends to be of a sexual nature, some of it no doubt issuing from the Sunnis' attitude toward "pleasure marriage," a Shia prerogative entitling men to engage a temporary union, which is effectively religiously sanctioned prostitution.