Would you rather die by a chemical weapon or by a machine gun? For myself I'd just rather not die.
It is worth remembering that the business of chemical weapons use being some sort of red line is a construct of Obama who had been talking tough on Syria while unable to back it up.
Now that chemical weapons have been used, and we still don't know by which side, remember, he seems to want to do something. He has let it be known that he is repositioning his Mediterranean Fleet.
For Obama to attack Syria without United Nations' approval, which means without Russian approval, would be utter folly. And on which side would he intervene? This is a civil war between a murderous autocrat and some murderous islamists.
Sometimes it's better to remain silent.