We have troops in Syria. They can also be killed by chem weapons, or didn’t you know that?
Oddly, the stated policy of of the US is to retaliate with tacnukes if gas is used against our troops.
See https://en.wikipedia.org/wiki/Atomic_demolition_munition to see just how small the munitions can be made...
Better choice - **remove ALL US troops from Syria**. Easy fix, no cruise missiles needed.