I'm not sure of the value add by any US strike as a supposed punishment of the Assad regime.

This Article provides a commentary on the apparent results of prior attempts to "punish" bad actors in the region.

I cannot comment on the source, but I will note that writers discussing punishment say that punishment has the following goals--deterrence, incapacitation, rehabilitation, reparation, and retribution/revenge. I'm not sure how launching a number of TLAMs at Syria meets any of them.