A more practical measure I've heard discussed is destroying or majorly disrupting Syrian air forces, which are concentrated within 6 or so major fixed installat

A more practical measure I've heard discussed is destroying or majorly disrupting Syrian air forces, which are concentrated within 6 or so major fixed installations, all of which can be targeted from standoff distance by U.S. ships and aircraft. In theory it would manage to deliver a firm "ouch" to incentivize more acceptable behavior without risking much in the way of escalation (as Syria has nothing they could strike the U.S. back with), and without meddling too much with the civil war proper (which is increasingly turning sectarian in nature). Of course there's still the large concern for Israel, but I don't see how pissing off the IDF helps Assad's chances either, and I think he recognizes that as well. But I don't think they are seriously considering targeting chemical stockpiles, as to do that properly would requires at least some ground-based forces.