insufficient respect

A dozen bad reasons for staying out of Syria
"It will only make things worse."

"This is insidious because the truth is no one knows the ultimate effects of any sort of intervention.  It gets plausibility from imagining all sorts of terrible but possible outcomes.   But if you imagine such outcomes, rationality also commands that you imagine no less probable good outcomes

Maybe Assad is on the verge of collapse, and his fall will be followed by the establishment of a democratic state, with minimal strife.   Maybe there will be strife, but neighboring and Western powers will easily find allies in Syria and contain it.  Maybe the 'Al Qaeda' Islamists will dissolve because much of their membership simply joined up to fight Assad, and the rest fritter away their strength in infighting.  Maybe a successful revolution in Syria will re-kindle the 'Arab Spring' and re-invigorate the whole region.   Or maybe not, but these are no less plausible outcomes than the doom-and-gloom scenarios, some of which will be examined below.

It's also worth asking just what is meant by 'making things worse'.   If the US delivers substantial support to the Free Syrian Army, OF COURSE things will get worse, because they will win, and before they win the fighting will intensify.  After that it will get much much better, because the fighting will end.  As for sectarian warfare, see below, on Islamists."