"A good number of them that live in the cities support Assad"? Based on what data? Didn't Hafez massacre a small city in the 80's? Also you're just going to write off the rural populaces grievances with a sentence attributing their malcontent to being religious conservatives? In my experience the world doesn't work that way. I suspect if you looked into the matter there would be economic and larger social factors at work. I also think you were a Sanders supporter so that makes your argument even that more puzzling to me. Baghdad alienating the Sunnis? I think the word you're looking for is oppressing? Maliki is largely responsible for the Sunni and Kurdish pain and anger in Iraq today. It wasn't only the Sunnis in Iraq who were given a bad hand from Baghdad. It's interesting you would argue for majority rule in Iraq but not in Syria. One would almost think you're acting in bad faith.
The sunni merchant class,industrialist,officer class all support Assad. There is a reason why the rebels have not been able to seize Aleppo or Damascus back 2012 in the initial offensives. They were composed of rural Sunnis who were seen as invaders by the urban sunnis. It would be like if rednecks in Pennsylvania trying to seize Philly. They share nothing in common with the people in the cities culturally.
So when you remove the dictator who rules Syria? You do realise the strongest sunni rebels groups in Syria are as follows:
Ahrar al Sham-they say that democracy is for infidels and that they admire the Taliban way of rule.
Hayat Tahir al Sham aka Jabhat al Nusra- basically al Qaeda in Syria.
Anjad al Sham-another Salafi group
Turkistan Independence Party-another Salafist group
Jaish al Islam- another Salafist fighting force based in Damascus.
There is the reason why Obama didnt want to get involved in Syria. The moderates were too weak, the radicals were stronger and popular. These groups are the strongest rebel fighters and form the bulk of the rebel fighting force. Look at rebel controlled Idlib which is under sharia law. There is no good alternative to Assad. I am being a realist and saying that as of right now Assad should stay in power because the rebels are filled with sunni jihadist and are fragmented thus fighting amongst themselves. Which tells me Syria would be Libya 2.0 had they won. In Iraq the majority already rules. The US put them the Shia in power. If it was up to me we wouldn't invade Iraq to lead to that. But what is done is done.
The problem with you interventionist is you are fixated on overthrowing the govt but have no clue what comes next. This is what led to the mess in Iraq and Libya.
Basically it's
1. Arm sunni rebels
2. Overthrow Assad
3
4
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7. Liberal Democracy in Syria.
I suggest you to read this article
Washington's Sunni Myth and the Civil Wars in Syria and Iraq