As fun as it is to imagine that simply bombing the country to hell and back will resolve the problem is unlikely for the following reasons
. Civilians are entrenched across the country, air force backing would create thousands more casualties
. Any undetected weapons depots can be utilized even after a decimation level strike
Attempting to send soldiers in would likely have a mirrored response by Lebanon and other countries in what would likely become a proxy war
Never mind that the aftermath of the conflict will involve segregation attempts by the Kurdish, and courtesy of Assad’s forces repeated attacks on the Sunni majority may result in a genocide of religious and ethnic minorities.
That said there is a long list of things that could be done to reduce civilian casualties, this includes
. Properly funding refugee camps – as of the present the UN is having difficulties maintaining existing campshttp://www.bbc.co.uk/news/world-middle-east-22045451
. Provide funding to near governments (Jordan, Turkey and if really feeling adventurous Iraq and Lebanon) based on how many refugees they accept, this creates open border incentives
. Provide funding to syrian civilians enough to support a month outside the country, As many civilians don’t have enough savings to support them and most don’t want to flee into a life on the streets
. Provide medical supplies to civilians, in more dangerous areas I would recommend supplying gas masks. Which as I can get it online for 70$, I presume could be beat on a larger scalehttp://www.armynavysuperstores.com/gasmaskis.htm
. Provide food & water to civilians, Damaged infrastructure and instability mean water can be non-existent and food costs greatly inflated
. Provide highway patrols, In many civil wars citizens become trapped in cities, with highways not being secure from essentially thugs and pirates.
. Provide transportation in any empty vehicles once any previous function is achieved, these can either take people from dangerous zones into less dangerous zones or to the border