A village in Iraq, where the residents are hostile to the government. Attack with banned chemical weapons. Bodies rotting in the streets. Mass graves.

Saddam Hussein. And now, us.

If you're curious, our chemical weapon of choice is White Phosphorus. Report corroborated here...

More: A commenter writes that white phosphorus is not a poison gas, and is a chemical weapon only to the extent that like anything else, it's made of chemicals. Fair enough. Incendiaries like White Phosphorus (and the new, improved napalm that we've also admitted to using) have been widely criticized as inhumane, and indiscriminately kill anyone even close to the impact point. As with poison gases, it's difficult to imagine using them without inflicting horrible death on innocent bystanders, particularly in an urban environment. Both incendiaries and poison gases are banned by international treaty. But the US has not signed on to the treaty that bans the incendiaries. So, to that extent, there certainly is a distinction...

(... BTW, the comment seems to be gone now. I'm not quite sure how that happened; it was not my intent...)