You cover a lot of ground there, but here's few points.
The danger to US troops is probably the least persuasive element of your argument. Iraq is by far the weakest of it's neighbors. It has very small numbers of chemical and biological munitions, according to even US sources, mostly weaponized as artillery shells. It only has hundreds where it would need many thousands and has focused on hiding such weapons rather than deploying them. Iraq's weapons of mass destruction are only potential ones, his mobile bio-weapons labs are a danger for the future, but he has shit right now.
During the Gulf War, a far more powerful Saddam ordered chemical weapons used. Nothing happened because the central command could no longer reach unit commanders. Their communications infrastructure was dismantled by focused US attacks. The same thing will happen again except much faster. The US has some new toys just for the job.