"In fact, as has now become clear, much of the opposition were and are ruthless sectarian fanatics, and Assad had majority support"
Simplistic in the extreme i'm afraid Mac.
The Assad family have been imprisoning, torturing and 'disappearing' opposition to its regime for decades - the West have been fully aware of this, certainly since the Amnesty report was published several years prior to the Arab Spring protests - that report contained descriptions of systematic arrests, torture of those arrested and then killing of anybody opposing the Syrian Government - it was this that largely led to the protests, which were brutally put down, Homs being the most memorable.
The protests were peaceful and were put down by extreme force, so much so that the U.N. made a move to intervene - vetoed by China and Russia.
The West refused to intervene, the slaughter continued and developed into civil war.
Inaction on the part of the West led to international disaffection by Muslims, who volunteered to support the opposition - Isis became part of this and came to prominence from the indifference of the West to the plight of the Syria people at the hands of Assad.
It would be appalling if Assad were to come out of this with clean hands and allowed to return to his old ways - where that to happen, the slaughter of his opponents would be unimaginable.
Jim Carroll