For Alawite Assad it makes sense to protect Christians- and other minority ethnicities and religions. The Akawites are officially regarded as a Shiite offshoot but it is questionable whether they are even Moslem. Iran accepts the Alawites as Shia because Iran needs Assad as an ally. A Sunni rebel victory in Syria would be disastrous for the Yezidis, the Kurds, Sufis, Druzes, and Shiites in Syria as well as for the Alawites and would cut off Iran’s free use of the area to transmit troops and supplies to its puppets and agents in Palestine and Jordan. Assad’s support is those minority groups. The Obama crusade (lunade?) to kill Assad was an attempt to purify Syria and purge these heretical and infidel minorities. It is what he would have liked to do to America.
Assad is a ruthless dictator. All others in the Middle East are dictators (Israel excepted) and only differ in their degrees of ruthlessness.
Prior to the war in Syria instigated by mostly outside forces, a Christian, a Jew or a Muslim could walk the streets in safety and pray at their own church, mosque or synagod in safety. All three also lived in the same communities and engaged in business and commerce together.
It should also be noted that the Christians in Syria are fighting in Assad’s Syrian Army for Assad. There are even some Christian Generals in the Syrian Army, including its Chief of Staff.
As mentioned, Assad is not a good guy but his enemies are far worse. Why are we fighting him?