"Chemical weapons can very effectively murder masses of people, all while the people using them can be out of harms way with gas masks and such." Cruise missiles can very effectively murder masses of people, all the while the people using them are safe on a boat in the middle of the sea. "Chemicals can also effect a wider range of people and do so over an extended period of time. Some chemical weapons cause cancer, which may not be apparent for many many years." Depleted uranium rounds effect a wider range of people and do so over an extended period of time. They cause cancer and birth defects, which are often not apparent for many years. "The chemical warfare that we are seeing in Syria is military vs civilians" All the warfare we are seeing in Syria is military vs. civilian. It is a civil war.
You're absolutely right. I'm just making some observations to try to shed light on why we suddenly political leaders around the globe are ready to step in and the media is having a field day with the 24/7 coverage. I think what it comes down to is the perceived difference between the two, rather than the actual difference.